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# [`string`](#module-string "string: Common string operations.") --- 常见的字符串操作
**源代码：** [Lib/string.py](https://github.com/python/cpython/tree/3.7/Lib/string.py) \[https://github.com/python/cpython/tree/3.7/Lib/string.py\]
- - - - - -
参见
[文本序列类型 --- str](stdtypes.xhtml#textseq)
[字符串的方法](stdtypes.xhtml#string-methods)
## 字符串常量
此模块中定义的常量为：
`string.``ascii_letters`The concatenation of the [`ascii_lowercase`](#string.ascii_lowercase "string.ascii_lowercase") and [`ascii_uppercase`](#string.ascii_uppercase "string.ascii_uppercase")constants described below. This value is not locale-dependent.
`string.``ascii_lowercase`The lowercase letters `'abcdefghijklmnopqrstuvwxyz'`. This value is not locale-dependent and will not change.
`string.``ascii_uppercase`The uppercase letters `'ABCDEFGHIJKLMNOPQRSTUVWXYZ'`. This value is not locale-dependent and will not change.
`string.``digits`字符串 `'0123456789'`。
`string.``hexdigits`字符串 `'0123456789abcdefABCDEF'`。
`string.``octdigits`字符串 `'01234567'`。
`string.``punctuation`String of ASCII characters which are considered punctuation characters in the `C` locale.
`string.``printable`String of ASCII characters which are considered printable. This is a combination of [`digits`](#string.digits "string.digits"), [`ascii_letters`](#string.ascii_letters "string.ascii_letters"), [`punctuation`](#string.punctuation "string.punctuation"), and [`whitespace`](#string.whitespace "string.whitespace").
`string.``whitespace`A string containing all ASCII characters that are considered whitespace. This includes the characters space, tab, linefeed, return, formfeed, and vertical tab.
## 自定义字符串格式
The built-in string class provides the ability to do complex variable substitutions and value formatting via the [`format()`](stdtypes.xhtml#str.format "str.format") method described in [**PEP 3101**](https://www.python.org/dev/peps/pep-3101) \[https://www.python.org/dev/peps/pep-3101\]. The [`Formatter`](#string.Formatter "string.Formatter") class in the [`string`](#module-string "string: Common string operations.") module allows you to create and customize your own string formatting behaviors using the same implementation as the built-in [`format()`](stdtypes.xhtml#str.format "str.format") method.
*class* `string.``Formatter`The [`Formatter`](#string.Formatter "string.Formatter") class has the following public methods:
`format`(*format\_string*, *\*args*, *\*\*kwargs*)The primary API method. It takes a format string and an arbitrary set of positional and keyword arguments. It is just a wrapper that calls [`vformat()`](#string.Formatter.vformat "string.Formatter.vformat").
在 3.7 版更改: A format string argument is now [positional-only](../glossary.xhtml#positional-only-parameter).
`vformat`(*format\_string*, *args*, *kwargs*)This function does the actual work of formatting. It is exposed as a separate function for cases where you want to pass in a predefined dictionary of arguments, rather than unpacking and repacking the dictionary as individual arguments using the `*args` and `**kwargs`syntax. [`vformat()`](#string.Formatter.vformat "string.Formatter.vformat") does the work of breaking up the format string into character data and replacement fields. It calls the various methods described below.
In addition, the [`Formatter`](#string.Formatter "string.Formatter") defines a number of methods that are intended to be replaced by subclasses:
`parse`(*format\_string*)Loop over the format\_string and return an iterable of tuples (*literal\_text*, *field\_name*, *format\_spec*, *conversion*). This is used by [`vformat()`](#string.Formatter.vformat "string.Formatter.vformat") to break the string into either literal text, or replacement fields.
The values in the tuple conceptually represent a span of literal text followed by a single replacement field. If there is no literal text (which can happen if two replacement fields occur consecutively), then *literal\_text* will be a zero-length string. If there is no replacement field, then the values of *field\_name*, *format\_spec* and *conversion*will be `None`.
`get_field`(*field\_name*, *args*, *kwargs*)Given *field\_name* as returned by [`parse()`](#string.Formatter.parse "string.Formatter.parse") (see above), convert it to an object to be formatted. Returns a tuple (obj, used\_key). The default version takes strings of the form defined in [**PEP 3101**](https://www.python.org/dev/peps/pep-3101) \[https://www.python.org/dev/peps/pep-3101\], such as "0\[name\]" or "label.title". *args* and *kwargs* are as passed in to [`vformat()`](#string.Formatter.vformat "string.Formatter.vformat"). The return value *used\_key* has the same meaning as the *key* parameter to [`get_value()`](#string.Formatter.get_value "string.Formatter.get_value").
`get_value`(*key*, *args*, *kwargs*)Retrieve a given field value. The *key* argument will be either an integer or a string. If it is an integer, it represents the index of the positional argument in *args*; if it is a string, then it represents a named argument in *kwargs*.
The *args* parameter is set to the list of positional arguments to [`vformat()`](#string.Formatter.vformat "string.Formatter.vformat"), and the *kwargs* parameter is set to the dictionary of keyword arguments.
For compound field names, these functions are only called for the first component of the field name; Subsequent components are handled through normal attribute and indexing operations.
So for example, the field expression '0.name' would cause [`get_value()`](#string.Formatter.get_value "string.Formatter.get_value") to be called with a *key* argument of 0. The `name`attribute will be looked up after [`get_value()`](#string.Formatter.get_value "string.Formatter.get_value") returns by calling the built-in [`getattr()`](functions.xhtml#getattr "getattr") function.
If the index or keyword refers to an item that does not exist, then an [`IndexError`](exceptions.xhtml#IndexError "IndexError") or [`KeyError`](exceptions.xhtml#KeyError "KeyError") should be raised.
`check_unused_args`(*used\_args*, *args*, *kwargs*)Implement checking for unused arguments if desired. The arguments to this function is the set of all argument keys that were actually referred to in the format string (integers for positional arguments, and strings for named arguments), and a reference to the *args* and *kwargs* that was passed to vformat. The set of unused args can be calculated from these parameters. [`check_unused_args()`](#string.Formatter.check_unused_args "string.Formatter.check_unused_args") is assumed to raise an exception if the check fails.
`format_field`(*value*, *format\_spec*)[`format_field()`](#string.Formatter.format_field "string.Formatter.format_field") simply calls the global [`format()`](functions.xhtml#format "format") built-in. The method is provided so that subclasses can override it.
`convert_field`(*value*, *conversion*)Converts the value (returned by [`get_field()`](#string.Formatter.get_field "string.Formatter.get_field")) given a conversion type (as in the tuple returned by the [`parse()`](#string.Formatter.parse "string.Formatter.parse") method). The default version understands 's' (str), 'r' (repr) and 'a' (ascii) conversion types.
## 格式字符串语法
The [`str.format()`](stdtypes.xhtml#str.format "str.format") method and the [`Formatter`](#string.Formatter "string.Formatter") class share the same syntax for format strings (although in the case of [`Formatter`](#string.Formatter "string.Formatter"), subclasses can define their own format string syntax). The syntax is related to that of [formatted string literals](../reference/lexical_analysis.xhtml#f-strings), but there are differences.
Format strings contain "replacement fields" surrounded by curly braces `{}`. Anything that is not contained in braces is considered literal text, which is copied unchanged to the output. If you need to include a brace character in the literal text, it can be escaped by doubling: `{{` and `}}`.
The grammar for a replacement field is as follows:
> ```
>
> replacement_field ::= "{" [field_name] ["!" conversion] [":" format_spec] "}"
> field_name ::= arg_name ("." attribute_name | "[" element_index "]")*
> arg_name ::= [identifier | digit+]
> attribute_name ::= identifier
> element_index ::= digit+ | index_string
> index_string ::= <any source character except "]"> +
> conversion ::= "r" | "s" | "a"
> format_spec ::= <described in the next section>
>
> ```
In less formal terms, the replacement field can start with a *field\_name* that specifies the object whose value is to be formatted and inserted into the output instead of the replacement field. The *field\_name* is optionally followed by a *conversion* field, which is preceded by an exclamation point `'!'`, and a *format\_spec*, which is preceded by a colon `':'`. These specify a non-default format for the replacement value.
See also the [Format Specification Mini-Language](#formatspec) section.
The *field\_name* itself begins with an *arg\_name* that is either a number or a keyword. If it's a number, it refers to a positional argument, and if it's a keyword, it refers to a named keyword argument. If the numerical arg\_names in a format string are 0, 1, 2, ... in sequence, they can all be omitted (not just some) and the numbers 0, 1, 2, ... will be automatically inserted in that order. Because *arg\_name* is not quote-delimited, it is not possible to specify arbitrary dictionary keys (e.g., the strings `'10'` or `':-]'`) within a format string. The *arg\_name* can be followed by any number of index or attribute expressions. An expression of the form `'.name'` selects the named attribute using [`getattr()`](functions.xhtml#getattr "getattr"), while an expression of the form `'[index]'`does an index lookup using [`__getitem__()`](../reference/datamodel.xhtml#object.__getitem__ "object.__getitem__").
在 3.1 版更改: The positional argument specifiers can be omitted for [`str.format()`](stdtypes.xhtml#str.format "str.format"), so `'{} {}'.format(a, b)` is equivalent to `'{0} {1}'.format(a, b)`.
在 3.4 版更改: The positional argument specifiers can be omitted for [`Formatter`](#string.Formatter "string.Formatter").
一些简单的格式字符串示例
```
"First, thou shalt count to {0}" # References first positional argument
"Bring me a {}" # Implicitly references the first positional argument
"From {} to {}" # Same as "From {0} to {1}"
"My quest is {name}" # References keyword argument 'name'
"Weight in tons {0.weight}" # 'weight' attribute of first positional arg
"Units destroyed: {players[0]}" # First element of keyword argument 'players'.
```
The *conversion* field causes a type coercion before formatting. Normally, the job of formatting a value is done by the [`__format__()`](../reference/datamodel.xhtml#object.__format__ "object.__format__") method of the value itself. However, in some cases it is desirable to force a type to be formatted as a string, overriding its own definition of formatting. By converting the value to a string before calling [`__format__()`](../reference/datamodel.xhtml#object.__format__ "object.__format__"), the normal formatting logic is bypassed.
Three conversion flags are currently supported: `'!s'` which calls [`str()`](stdtypes.xhtml#str "str")on the value, `'!r'` which calls [`repr()`](functions.xhtml#repr "repr") and `'!a'` which calls [`ascii()`](functions.xhtml#ascii "ascii").
几个例子：
```
"Harold's a clever {0!s}" # Calls str() on the argument first
"Bring out the holy {name!r}" # Calls repr() on the argument first
"More {!a}" # Calls ascii() on the argument first
```
The *format\_spec* field contains a specification of how the value should be presented, including such details as field width, alignment, padding, decimal precision and so on. Each value type can define its own "formatting mini-language" or interpretation of the *format\_spec*.
Most built-in types support a common formatting mini-language, which is described in the next section.
A *format\_spec* field can also include nested replacement fields within it. These nested replacement fields may contain a field name, conversion flag and format specification, but deeper nesting is not allowed. The replacement fields within the format\_spec are substituted before the *format\_spec* string is interpreted. This allows the formatting of a value to be dynamically specified.
See the [Format examples](#formatexamples) section for some examples.
### Format Specification Mini-Language
"Format specifications" are used within replacement fields contained within a format string to define how individual values are presented (see [格式字符串语法](#formatstrings) and [格式化字符串字面值](../reference/lexical_analysis.xhtml#f-strings)). They can also be passed directly to the built-in [`format()`](functions.xhtml#format "format") function. Each formattable type may define how the format specification is to be interpreted.
Most built-in types implement the following options for format specifications, although some of the formatting options are only supported by the numeric types.
A general convention is that an empty format string (`""`) produces the same result as if you had called [`str()`](stdtypes.xhtml#str "str") on the value. A non-empty format string typically modifies the result.
The general form of a *standard format specifier* is:
```
format_spec ::= [[fill]align][sign][#][0][width][grouping_option][.precision][type]
fill ::= <any character>
align ::= "<" | ">" | "=" | "^"
sign ::= "+" | "-" | " "
width ::= digit+
grouping_option ::= "_" | ","
precision ::= digit+
type ::= "b" | "c" | "d" | "e" | "E" | "f" | "F" | "g" | "G" | "n" | "o" | "s" | "x" | "X" | "%"
```
If a valid *align* value is specified, it can be preceded by a *fill*character that can be any character and defaults to a space if omitted. It is not possible to use a literal curly brace ("`{`" or "`}`") as the *fill* character in a [formatted string literal](../reference/lexical_analysis.xhtml#f-strings) or when using the [`str.format()`](stdtypes.xhtml#str.format "str.format")method. However, it is possible to insert a curly brace with a nested replacement field. This limitation doesn't affect the [`format()`](functions.xhtml#format "format") function.
The meaning of the various alignment options is as follows:
> 选项
>
> 意义
>
> `'<'`
>
> 强制字段在可用空间内左对齐（这是大多数对象的默认值）。
>
> `'>'`
>
> 强制字段在可用空间内右对齐（这是数字的默认值）。
>
> `'='`
>
> 强制将填充放置在符号（如果有）之后但在数字之前。这用于以“+000000120”形式打印字段。此对齐选项仅对数字类型有效。当'0'紧接在字段宽度之前时，它成为默认值。
>
> `'^'`
>
> 强制字段在可用空间内居中。
请注意，除非定义了最小字段宽度，否则字段宽度将始终与填充它的数据大小相同，因此在这种情况下，对齐选项没有意义。
*sign* 选项仅对数字类型有效，可以是以下之一：
> 选项
>
> 意义
>
> `'+'`
>
> 表示标志应该用于正数和负数。
>
> `'-'`
>
> 表示标志应仅用于负数（这是默认行为）。
>
> space
>
> 表示应在正数上使用前导空格，在负数上使用减号。
The `'#'` option causes the "alternate form" to be used for the conversion. The alternate form is defined differently for different types. This option is only valid for integer, float, complex and Decimal types. For integers, when binary, octal, or hexadecimal output is used, this option adds the prefix respective `'0b'`, `'0o'`, or `'0x'` to the output value. For floats, complex and Decimal the alternate form causes the result of the conversion to always contain a decimal-point character, even if no digits follow it. Normally, a decimal-point character appears in the result of these conversions only if a digit follows it. In addition, for `'g'` and `'G'`conversions, trailing zeros are not removed from the result.
The `','` option signals the use of a comma for a thousands separator. For a locale aware separator, use the `'n'` integer presentation type instead.
在 3.1 版更改: Added the `','` option (see also [**PEP 378**](https://www.python.org/dev/peps/pep-0378) \[https://www.python.org/dev/peps/pep-0378\]).
The `'_'` option signals the use of an underscore for a thousands separator for floating point presentation types and for integer presentation type `'d'`. For integer presentation types `'b'`, `'o'`, `'x'`, and `'X'`, underscores will be inserted every 4 digits. For other presentation types, specifying this option is an error.
在 3.6 版更改: Added the `'_'` option (see also [**PEP 515**](https://www.python.org/dev/peps/pep-0515) \[https://www.python.org/dev/peps/pep-0515\]).
*width* is a decimal integer defining the minimum field width. If not specified, then the field width will be determined by the content.
When no explicit alignment is given, preceding the *width* field by a zero (`'0'`) character enables sign-aware zero-padding for numeric types. This is equivalent to a *fill*character of `'0'` with an *alignment* type of `'='`.
The *precision* is a decimal number indicating how many digits should be displayed after the decimal point for a floating point value formatted with `'f'` and `'F'`, or before and after the decimal point for a floating point value formatted with `'g'` or `'G'`. For non-number types the field indicates the maximum field size - in other words, how many characters will be used from the field content. The *precision* is not allowed for integer values.
Finally, the *type* determines how the data should be presented.
可用的字符串表示类型是：
> 类型
>
> 意义
>
> `'s'`
>
> 字符串格式。这是字符串的默认类型，可以省略。
>
> None
>
> 和 `'s'` 一样。
可用的整数表示类型是：
> 类型
>
> 意义
>
> `'b'`
>
> 二进制格式。输出基数2中的数字。
>
> `'c'`
>
> 字符。在打印之前将整数转换为相应的unicode字符。
>
> `'d'`
>
> 十进制整数。输出基数为10的数字。
>
> `'o'`
>
> 八进制格式。输出基数为8的数字。
>
> `'x'`
>
> 十六进制格式输出基数为16的数字，使用小写字母表示9以上的数字。
>
> `'X'`
>
> 十六进制格式输出基数16中的数字，使用大写字母表示9以上的数字。
>
> `'n'`
>
> Number. This is the same as `'d'`, except that it uses the current locale setting to insert the appropriate number separator characters.
>
> None
>
> 和 `'d'` 一样。
In addition to the above presentation types, integers can be formatted with the floating point presentation types listed below (except `'n'` and `None`). When doing so, [`float()`](functions.xhtml#float "float") is used to convert the integer to a floating point number before formatting.
The available presentation types for floating point and decimal values are:
> 类型
>
> 意义
>
> `'e'`
>
> Exponent notation. Prints the number in scientific notation using the letter 'e' to indicate the exponent. The default precision is `6`.
>
> `'E'`
>
> Exponent notation. Same as `'e'` except it uses an upper case 'E' as the separator character.
>
> `'f'`
>
> Fixed-point notation. Displays the number as a fixed-point number. The default precision is `6`.
>
> `'F'`
>
> Fixed-point notation. Same as `'f'`, but converts `nan` to `NAN` and `inf` to `INF`.
>
> `'g'`
>
> General format. For a given precision `p >= 1`, this rounds the number to `p` significant digits and then formats the result in either fixed-point format or in scientific notation, depending on its magnitude.
>
> The precise rules are as follows: suppose that the result formatted with presentation type `'e'` and precision `p-1` would have exponent `exp`. Then if `-4 <= exp < p`, the number is formatted with presentation type `'f'` and precision `p-1-exp`. Otherwise, the number is formatted with presentation type `'e'` and precision `p-1`. In both cases insignificant trailing zeros are removed from the significand, and the decimal point is also removed if there are no remaining digits following it.
>
> Positive and negative infinity, positive and negative zero, and nans, are formatted as `inf`, `-inf`, `0`, `-0` and `nan` respectively, regardless of the precision.
>
> A precision of `0` is treated as equivalent to a precision of `1`. The default precision is `6`.
>
> `'G'`
>
> General format. Same as `'g'` except switches to `'E'` if the number gets too large. The representations of infinity and NaN are uppercased, too.
>
> `'n'`
>
> Number. This is the same as `'g'`, except that it uses the current locale setting to insert the appropriate number separator characters.
>
> `'%'`
>
> Percentage. Multiplies the number by 100 and displays in fixed (`'f'`) format, followed by a percent sign.
>
> None
>
> Similar to `'g'`, except that fixed-point notation, when used, has at least one digit past the decimal point. The default precision is as high as needed to represent the particular value. The overall effect is to match the output of [`str()`](stdtypes.xhtml#str "str") as altered by the other format modifiers.
### Format examples
This section contains examples of the [`str.format()`](stdtypes.xhtml#str.format "str.format") syntax and comparison with the old `%`-formatting.
In most of the cases the syntax is similar to the old `%`-formatting, with the addition of the `{}` and with `:` used instead of `%`. For example, `'%03.2f'` can be translated to `'{:03.2f}'`.
The new format syntax also supports new and different options, shown in the following examples.
Accessing arguments by position:
```
>>> '{0}, {1}, {2}'.format('a', 'b', 'c')
'a, b, c'
>>> '{}, {}, {}'.format('a', 'b', 'c') # 3.1+ only
'a, b, c'
>>> '{2}, {1}, {0}'.format('a', 'b', 'c')
'c, b, a'
>>> '{2}, {1}, {0}'.format(*'abc') # unpacking argument sequence
'c, b, a'
>>> '{0}{1}{0}'.format('abra', 'cad') # arguments' indices can be repeated
'abracadabra'
```
Accessing arguments by name:
```
>>> 'Coordinates: {latitude}, {longitude}'.format(latitude='37.24N', longitude='-115.81W')
'Coordinates: 37.24N, -115.81W'
>>> coord = {'latitude': '37.24N', 'longitude': '-115.81W'}
>>> 'Coordinates: {latitude}, {longitude}'.format(**coord)
'Coordinates: 37.24N, -115.81W'
```
Accessing arguments' attributes:
```
>>> c = 3-5j
>>> ('The complex number {0} is formed from the real part {0.real} '
... 'and the imaginary part {0.imag}.').format(c)
'The complex number (3-5j) is formed from the real part 3.0 and the imaginary part -5.0.'
>>> class Point:
... def __init__(self, x, y):
... self.x, self.y = x, y
... def __str__(self):
... return 'Point({self.x}, {self.y})'.format(self=self)
...
>>> str(Point(4, 2))
'Point(4, 2)'
```
Accessing arguments' items:
```
>>> coord = (3, 5)
>>> 'X: {0[0]}; Y: {0[1]}'.format(coord)
'X: 3; Y: 5'
```
Replacing `%s` and `%r`:
```
>>> "repr() shows quotes: {!r}; str() doesn't: {!s}".format('test1', 'test2')
"repr() shows quotes: 'test1'; str() doesn't: test2"
```
Aligning the text and specifying a width:
```
>>> '{:<30}'.format('left aligned')
'left aligned '
>>> '{:>30}'.format('right aligned')
' right aligned'
>>> '{:^30}'.format('centered')
' centered '
>>> '{:*^30}'.format('centered') # use '*' as a fill char
'***********centered***********'
```
Replacing `%+f`, `%-f`, and `% f` and specifying a sign:
```
>>> '{:+f}; {:+f}'.format(3.14, -3.14) # show it always
'+3.140000; -3.140000'
>>> '{: f}; {: f}'.format(3.14, -3.14) # show a space for positive numbers
' 3.140000; -3.140000'
>>> '{:-f}; {:-f}'.format(3.14, -3.14) # show only the minus -- same as '{:f}; {:f}'
'3.140000; -3.140000'
```
Replacing `%x` and `%o` and converting the value to different bases:
```
>>> # format also supports binary numbers
>>> "int: {0:d}; hex: {0:x}; oct: {0:o}; bin: {0:b}".format(42)
'int: 42; hex: 2a; oct: 52; bin: 101010'
>>> # with 0x, 0o, or 0b as prefix:
>>> "int: {0:d}; hex: {0:#x}; oct: {0:#o}; bin: {0:#b}".format(42)
'int: 42; hex: 0x2a; oct: 0o52; bin: 0b101010'
```
Using the comma as a thousands separator:
```
>>> '{:,}'.format(1234567890)
'1,234,567,890'
```
Expressing a percentage:
```
>>> points = 19
>>> total = 22
>>> 'Correct answers: {:.2%}'.format(points/total)
'Correct answers: 86.36%'
```
Using type-specific formatting:
```
>>> import datetime
>>> d = datetime.datetime(2010, 7, 4, 12, 15, 58)
>>> '{:%Y-%m-%d %H:%M:%S}'.format(d)
'2010-07-04 12:15:58'
```
Nesting arguments and more complex examples:
```
>>> for align, text in zip('<^>', ['left', 'center', 'right']):
... '{0:{fill}{align}16}'.format(text, fill=align, align=align)
...
'left<<<<<<<<<<<<'
'^^^^^center^^^^^'
'>>>>>>>>>>>right'
>>>
>>> octets = [192, 168, 0, 1]
>>> '{:02X}{:02X}{:02X}{:02X}'.format(*octets)
'C0A80001'
>>> int(_, 16)
3232235521
>>>
>>> width = 5
>>> for num in range(5,12):
... for base in 'dXob':
... print('{0:{width}{base}}'.format(num, base=base, width=width), end=' ')
... print()
...
5 5 5 101
6 6 6 110
7 7 7 111
8 8 10 1000
9 9 11 1001
10 A 12 1010
11 B 13 1011
```
## Template strings
Template strings provide simpler string substitutions as described in [**PEP 292**](https://www.python.org/dev/peps/pep-0292) \[https://www.python.org/dev/peps/pep-0292\]. A primary use case for template strings is for internationalization (i18n) since in that context, the simpler syntax and functionality makes it easier to translate than other built-in string formatting facilities in Python. As an example of a library built on template strings for i18n, see the [flufl.i18n](http://flufli18n.readthedocs.io/en/latest/) \[http://flufli18n.readthedocs.io/en/latest/\] package.
Template strings support `$`-based substitutions, using the following rules:
- `$$` is an escape; it is replaced with a single `$`.
- `$identifier` names a substitution placeholder matching a mapping key of `"identifier"`. By default, `"identifier"` is restricted to any case-insensitive ASCII alphanumeric string (including underscores) that starts with an underscore or ASCII letter. The first non-identifier character after the `$` character terminates this placeholder specification.
- `${identifier}` is equivalent to `$identifier`. It is required when valid identifier characters follow the placeholder but are not part of the placeholder, such as `"${noun}ification"`.
Any other appearance of `$` in the string will result in a [`ValueError`](exceptions.xhtml#ValueError "ValueError")being raised.
The [`string`](#module-string "string: Common string operations.") module provides a [`Template`](#string.Template "string.Template") class that implements these rules. The methods of [`Template`](#string.Template "string.Template") are:
*class* `string.``Template`(*template*)The constructor takes a single argument which is the template string.
`substitute`(*mapping*, *\*\*kwds*)Performs the template substitution, returning a new string. *mapping* is any dictionary-like object with keys that match the placeholders in the template. Alternatively, you can provide keyword arguments, where the keywords are the placeholders. When both *mapping* and *kwds* are given and there are duplicates, the placeholders from *kwds* take precedence.
`safe_substitute`(*mapping*, *\*\*kwds*)Like [`substitute()`](#string.Template.substitute "string.Template.substitute"), except that if placeholders are missing from *mapping* and *kwds*, instead of raising a [`KeyError`](exceptions.xhtml#KeyError "KeyError") exception, the original placeholder will appear in the resulting string intact. Also, unlike with [`substitute()`](#string.Template.substitute "string.Template.substitute"), any other appearances of the `$` will simply return `$` instead of raising [`ValueError`](exceptions.xhtml#ValueError "ValueError").
While other exceptions may still occur, this method is called "safe" because it always tries to return a usable string instead of raising an exception. In another sense, [`safe_substitute()`](#string.Template.safe_substitute "string.Template.safe_substitute") may be anything other than safe, since it will silently ignore malformed templates containing dangling delimiters, unmatched braces, or placeholders that are not valid Python identifiers.
[`Template`](#string.Template "string.Template") instances also provide one public data attribute:
`template`This is the object passed to the constructor's *template* argument. In general, you shouldn't change it, but read-only access is not enforced.
Here is an example of how to use a Template:
```
>>> from string import Template
>>> s = Template('$who likes $what')
>>> s.substitute(who='tim', what='kung pao')
'tim likes kung pao'
>>> d = dict(who='tim')
>>> Template('Give $who $100').substitute(d)
Traceback (most recent call last):
...
ValueError: Invalid placeholder in string: line 1, col 11
>>> Template('$who likes $what').substitute(d)
Traceback (most recent call last):
...
KeyError: 'what'
>>> Template('$who likes $what').safe_substitute(d)
'tim likes $what'
```
Advanced usage: you can derive subclasses of [`Template`](#string.Template "string.Template") to customize the placeholder syntax, delimiter character, or the entire regular expression used to parse template strings. To do this, you can override these class attributes:
- *delimiter* -- This is the literal string describing a placeholder introducing delimiter. The default value is `$`. Note that this should *not* be a regular expression, as the implementation will call [`re.escape()`](re.xhtml#re.escape "re.escape") on this string as needed. Note further that you cannot change the delimiter after class creation (i.e. a different delimiter must be set in the subclass's class namespace).
- *idpattern* -- This is the regular expression describing the pattern for non-braced placeholders. The default value is the regular expression `(?a:[_a-z][_a-z0-9]*)`. If this is given and *braceidpattern* is `None` this pattern will also apply to braced placeholders.
注解
Since default *flags* is `re.IGNORECASE`, pattern `[a-z]` can match with some non-ASCII characters. That's why we use the local `a` flag here.
在 3.7 版更改: *braceidpattern* can be used to define separate patterns used inside and outside the braces.
- *braceidpattern* -- This is like *idpattern* but describes the pattern for braced placeholders. Defaults to `None` which means to fall back to *idpattern* (i.e. the same pattern is used both inside and outside braces). If given, this allows you to define different patterns for braced and unbraced placeholders.
3\.7 新版功能.
- *flags* -- The regular expression flags that will be applied when compiling the regular expression used for recognizing substitutions. The default value is `re.IGNORECASE`. Note that `re.VERBOSE` will always be added to the flags, so custom *idpattern*s must follow conventions for verbose regular expressions.
3\.2 新版功能.
Alternatively, you can provide the entire regular expression pattern by overriding the class attribute *pattern*. If you do this, the value must be a regular expression object with four named capturing groups. The capturing groups correspond to the rules given above, along with the invalid placeholder rule:
- *escaped* -- This group matches the escape sequence, e.g. `$$`, in the default pattern.
- *named* -- This group matches the unbraced placeholder name; it should not include the delimiter in capturing group.
- *braced* -- This group matches the brace enclosed placeholder name; it should not include either the delimiter or braces in the capturing group.
- *invalid* -- This group matches any other delimiter pattern (usually a single delimiter), and it should appear last in the regular expression.
## Helper functions
`string.``capwords`(*s*, *sep=None*)Split the argument into words using [`str.split()`](stdtypes.xhtml#str.split "str.split"), capitalize each word using [`str.capitalize()`](stdtypes.xhtml#str.capitalize "str.capitalize"), and join the capitalized words using [`str.join()`](stdtypes.xhtml#str.join "str.join"). If the optional second argument *sep* is absent or `None`, runs of whitespace characters are replaced by a single space and leading and trailing whitespace are removed, otherwise *sep* is used to split and join the words.
### 导航
- [索引](../genindex.xhtml "总目录")
- [模块](../py-modindex.xhtml "Python 模块索引") |
- [下一页](re.xhtml "re --- 正则表达式操作") |
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- 其他内置类型
- 特殊属性
- 内置异常
- 基类
- 具体异常
- 警告
- 异常层次结构
- 文本处理服务
- string — 常见的字符串操作
- re — 正则表达式操作
- 模块 difflib 是一个计算差异的助手
- textwrap — Text wrapping and filling
- unicodedata — Unicode 数据库
- stringprep — Internet String Preparation
- readline — GNU readline interface
- rlcompleter — GNU readline的完成函数
- 二进制数据服务
- struct — Interpret bytes as packed binary data
- codecs — Codec registry and base classes
- 数据类型
- datetime — 基础日期/时间数据类型
- calendar — General calendar-related functions
- collections — 容器数据类型
- collections.abc — 容器的抽象基类
- heapq — 堆队列算法
- bisect — Array bisection algorithm
- array — Efficient arrays of numeric values
- weakref — 弱引用
- types — Dynamic type creation and names for built-in types
- copy — 浅层 (shallow) 和深层 (deep) 复制操作
- pprint — 数据美化输出
- reprlib — Alternate repr() implementation
- enum — Support for enumerations
- 数字和数学模块
- numbers — 数字的抽象基类
- math — 数学函数
- cmath — Mathematical functions for complex numbers
- decimal — 十进制定点和浮点运算
- fractions — 分数
- random — 生成伪随机数
- statistics — Mathematical statistics functions
- 函数式编程模块
- itertools — 为高效循环而创建迭代器的函数
- functools — 高阶函数和可调用对象上的操作
- operator — 标准运算符替代函数
- 文件和目录访问
- pathlib — 面向对象的文件系统路径
- os.path — 常见路径操作
- fileinput — Iterate over lines from multiple input streams
- stat — Interpreting stat() results
- filecmp — File and Directory Comparisons
- tempfile — Generate temporary files and directories
- glob — Unix style pathname pattern expansion
- fnmatch — Unix filename pattern matching
- linecache — Random access to text lines
- shutil — High-level file operations
- macpath — Mac OS 9 路径操作函数
- 数据持久化
- pickle —— Python 对象序列化
- copyreg — Register pickle support functions
- shelve — Python object persistence
- marshal — Internal Python object serialization
- dbm — Interfaces to Unix “databases”
- sqlite3 — SQLite 数据库 DB-API 2.0 接口模块
- 数据压缩和存档
- zlib — 与 gzip 兼容的压缩
- gzip — 对 gzip 格式的支持
- bz2 — 对 bzip2 压缩算法的支持
- lzma — 用 LZMA 算法压缩
- zipfile — 在 ZIP 归档中工作
- tarfile — Read and write tar archive files
- 文件格式
- csv — CSV 文件读写
- configparser — Configuration file parser
- netrc — netrc file processing
- xdrlib — Encode and decode XDR data
- plistlib — Generate and parse Mac OS X .plist files
- 加密服务
- hashlib — 安全哈希与消息摘要
- hmac — 基于密钥的消息验证
- secrets — Generate secure random numbers for managing secrets
- 通用操作系统服务
- os — 操作系统接口模块
- io — 处理流的核心工具
- time — 时间的访问和转换
- argparse — 命令行选项、参数和子命令解析器
- getopt — C-style parser for command line options
- 模块 logging — Python 的日志记录工具
- logging.config — 日志记录配置
- logging.handlers — Logging handlers
- getpass — 便携式密码输入工具
- curses — 终端字符单元显示的处理
- curses.textpad — Text input widget for curses programs
- curses.ascii — Utilities for ASCII characters
- curses.panel — A panel stack extension for curses
- platform — Access to underlying platform's identifying data
- errno — Standard errno system symbols
- ctypes — Python 的外部函数库
- 并发执行
- threading — 基于线程的并行
- multiprocessing — 基于进程的并行
- concurrent 包
- concurrent.futures — 启动并行任务
- subprocess — 子进程管理
- sched — 事件调度器
- queue — 一个同步的队列类
- _thread — 底层多线程 API
- _dummy_thread — _thread 的替代模块
- dummy_threading — 可直接替代 threading 模块。
- contextvars — Context Variables
- Context Variables
- Manual Context Management
- asyncio support
- 网络和进程间通信
- asyncio — 异步 I/O
- socket — 底层网络接口
- ssl — TLS/SSL wrapper for socket objects
- select — Waiting for I/O completion
- selectors — 高级 I/O 复用库
- asyncore — 异步socket处理器
- asynchat — 异步 socket 指令/响应 处理器
- signal — Set handlers for asynchronous events
- mmap — Memory-mapped file support
- 互联网数据处理
- email — 电子邮件与 MIME 处理包
- json — JSON 编码和解码器
- mailcap — Mailcap file handling
- mailbox — Manipulate mailboxes in various formats
- mimetypes — Map filenames to MIME types
- base64 — Base16, Base32, Base64, Base85 数据编码
- binhex — 对binhex4文件进行编码和解码
- binascii — 二进制和 ASCII 码互转
- quopri — Encode and decode MIME quoted-printable data
- uu — Encode and decode uuencode files
- 结构化标记处理工具
- html — 超文本标记语言支持
- html.parser — 简单的 HTML 和 XHTML 解析器
- html.entities — HTML 一般实体的定义
- XML处理模块
- xml.etree.ElementTree — The ElementTree XML API
- xml.dom — The Document Object Model API
- xml.dom.minidom — Minimal DOM implementation
- xml.dom.pulldom — Support for building partial DOM trees
- xml.sax — Support for SAX2 parsers
- xml.sax.handler — Base classes for SAX handlers
- xml.sax.saxutils — SAX Utilities
- xml.sax.xmlreader — Interface for XML parsers
- xml.parsers.expat — Fast XML parsing using Expat
- 互联网协议和支持
- webbrowser — 方便的Web浏览器控制器
- cgi — Common Gateway Interface support
- cgitb — Traceback manager for CGI scripts
- wsgiref — WSGI Utilities and Reference Implementation
- urllib — URL 处理模块
- urllib.request — 用于打开 URL 的可扩展库
- urllib.response — Response classes used by urllib
- urllib.parse — Parse URLs into components
- urllib.error — Exception classes raised by urllib.request
- urllib.robotparser — Parser for robots.txt
- http — HTTP 模块
- http.client — HTTP协议客户端
- ftplib — FTP protocol client
- poplib — POP3 protocol client
- imaplib — IMAP4 protocol client
- nntplib — NNTP protocol client
- smtplib —SMTP协议客户端
- smtpd — SMTP Server
- telnetlib — Telnet client
- uuid — UUID objects according to RFC 4122
- socketserver — A framework for network servers
- http.server — HTTP 服务器
- http.cookies — HTTP state management
- http.cookiejar — Cookie handling for HTTP clients
- xmlrpc — XMLRPC 服务端与客户端模块
- xmlrpc.client — XML-RPC client access
- xmlrpc.server — Basic XML-RPC servers
- ipaddress — IPv4/IPv6 manipulation library
- 多媒体服务
- audioop — Manipulate raw audio data
- aifc — Read and write AIFF and AIFC files
- sunau — 读写 Sun AU 文件
- wave — 读写WAV格式文件
- chunk — Read IFF chunked data
- colorsys — Conversions between color systems
- imghdr — 推测图像类型
- sndhdr — 推测声音文件的类型
- ossaudiodev — Access to OSS-compatible audio devices
- 国际化
- gettext — 多语种国际化服务
- locale — 国际化服务
- 程序框架
- turtle — 海龟绘图
- cmd — 支持面向行的命令解释器
- shlex — Simple lexical analysis
- Tk图形用户界面(GUI)
- tkinter — Tcl/Tk的Python接口
- tkinter.ttk — Tk themed widgets
- tkinter.tix — Extension widgets for Tk
- tkinter.scrolledtext — 滚动文字控件
- IDLE
- 其他图形用户界面（GUI）包
- 开发工具
- typing — 类型标注支持
- pydoc — Documentation generator and online help system
- doctest — Test interactive Python examples
- unittest — 单元测试框架
- unittest.mock — mock object library
- unittest.mock 上手指南
- 2to3 - 自动将 Python 2 代码转为 Python 3 代码
- test — Regression tests package for Python
- test.support — Utilities for the Python test suite
- test.support.script_helper — Utilities for the Python execution tests
- 调试和分析
- bdb — Debugger framework
- faulthandler — Dump the Python traceback
- pdb — The Python Debugger
- The Python Profilers
- timeit — 测量小代码片段的执行时间
- trace — Trace or track Python statement execution
- tracemalloc — Trace memory allocations
- 软件打包和分发
- distutils — 构建和安装 Python 模块
- ensurepip — Bootstrapping the pip installer
- venv — 创建虚拟环境
- zipapp — Manage executable Python zip archives
- Python运行时服务
- sys — 系统相关的参数和函数
- sysconfig — Provide access to Python's configuration information
- builtins — 内建对象
- main — 顶层脚本环境
- warnings — Warning control
- dataclasses — 数据类
- contextlib — Utilities for with-statement contexts
- abc — 抽象基类
- atexit — 退出处理器
- traceback — Print or retrieve a stack traceback
- future — Future 语句定义
- gc — 垃圾回收器接口
- inspect — 检查对象
- site — Site-specific configuration hook
- 自定义 Python 解释器
- code — Interpreter base classes
- codeop — Compile Python code
- 导入模块
- zipimport — Import modules from Zip archives
- pkgutil — Package extension utility
- modulefinder — 查找脚本使用的模块
- runpy — Locating and executing Python modules
- importlib — The implementation of import
- Python 语言服务
- parser — Access Python parse trees
- ast — 抽象语法树
- symtable — Access to the compiler's symbol tables
- symbol — 与 Python 解析树一起使用的常量
- token — 与Python解析树一起使用的常量
- keyword — 检验Python关键字
- tokenize — Tokenizer for Python source
- tabnanny — 模糊缩进检测
- pyclbr — Python class browser support
- py_compile — Compile Python source files
- compileall — Byte-compile Python libraries
- dis — Python 字节码反汇编器
- pickletools — Tools for pickle developers
- 杂项服务
- formatter — Generic output formatting
- Windows系统相关模块
- msilib — Read and write Microsoft Installer files
- msvcrt — Useful routines from the MS VC++ runtime
- winreg — Windows 注册表访问
- winsound — Sound-playing interface for Windows
- Unix 专有服务
- posix — The most common POSIX system calls
- pwd — 用户密码数据库
- spwd — The shadow password database
- grp — The group database
- crypt — Function to check Unix passwords
- termios — POSIX style tty control
- tty — 终端控制功能
- pty — Pseudo-terminal utilities
- fcntl — The fcntl and ioctl system calls
- pipes — Interface to shell pipelines
- resource — Resource usage information
- nis — Interface to Sun's NIS (Yellow Pages)
- Unix syslog 库例程
- 被取代的模块
- optparse — Parser for command line options
- imp — Access the import internals
- 未创建文档的模块
- 平台特定模块
- 扩展和嵌入 Python 解释器
- 推荐的第三方工具
- 不使用第三方工具创建扩展
- 使用 C 或 C++ 扩展 Python
- 自定义扩展类型：教程
- 定义扩展类型：已分类主题
- 构建C/C++扩展
- 在Windows平台编译C和C++扩展
- 在更大的应用程序中嵌入 CPython 运行时
- Embedding Python in Another Application
- Python/C API 参考手册
- 概述
- 代码标准
- 包含文件
- 有用的宏
- 对象、类型和引用计数
- 异常
- 嵌入Python
- 调试构建
- 稳定的应用程序二进制接口
- The Very High Level Layer
- Reference Counting
- 异常处理
- Printing and clearing
- 抛出异常
- Issuing warnings
- Querying the error indicator
- Signal Handling
- Exception Classes
- Exception Objects
- Unicode Exception Objects
- Recursion Control
- 标准异常
- 标准警告类别
- 工具
- 操作系统实用程序
- 系统功能
- 过程控制
- 导入模块
- Data marshalling support
- 语句解释及变量编译
- 字符串转换与格式化
- 反射
- 编解码器注册与支持功能
- 抽象对象层
- Object Protocol
- 数字协议
- Sequence Protocol
- Mapping Protocol
- 迭代器协议
- 缓冲协议
- Old Buffer Protocol
- 具体的对象层
- 基本对象
- 数值对象
- 序列对象
- 容器对象
- 函数对象
- 其他对象
- Initialization, Finalization, and Threads
- 在Python初始化之前
- 全局配置变量
- Initializing and finalizing the interpreter
- Process-wide parameters
- Thread State and the Global Interpreter Lock
- Sub-interpreter support
- Asynchronous Notifications
- Profiling and Tracing
- Advanced Debugger Support
- Thread Local Storage Support
- 内存管理
- 概述
- 原始内存接口
- Memory Interface
- 对象分配器
- 默认内存分配器
- Customize Memory Allocators
- The pymalloc allocator
- tracemalloc C API
- 示例
- 对象实现支持
- 在堆中分配对象
- Common Object Structures
- Type 对象
- Number Object Structures
- Mapping Object Structures
- Sequence Object Structures
- Buffer Object Structures
- Async Object Structures
- 使对象类型支持循环垃圾回收
- API 和 ABI 版本管理
- 分发 Python 模块
- 关键术语
- 开源许可与协作
- 安装工具
- 阅读指南
- 我该如何...？
- ...为我的项目选择一个名字？
- ...创建和分发二进制扩展？
- 安装 Python 模块
- 关键术语
- 基本使用
- 我应如何 ...？
- ... 在 Python 3.4 之前的 Python 版本中安装 pip ？
- ... 只为当前用户安装软件包？
- ... 安装科学计算类 Python 软件包？
- ... 使用并行安装的多个 Python 版本？
- 常见的安装问题
- 在 Linux 的系统 Python 版本上安装
- 未安装 pip
- 安装二进制编译扩展
- Python 常用指引
- 将 Python 2 代码迁移到 Python 3
- 简要说明
- 详情
- 将扩展模块移植到 Python 3
- 条件编译
- 对象API的更改
- 模块初始化和状态
- CObject 替换为 Capsule
- 其他选项
- Curses Programming with Python
- What is curses?
- Starting and ending a curses application
- Windows and Pads
- Displaying Text
- User Input
- For More Information
- 实现描述器
- 摘要
- 定义和简介
- 描述器协议
- 发起调用描述符
- 描述符示例
- Properties
- 函数和方法
- Static Methods and Class Methods
- 函数式编程指引
- 概述
- 迭代器
- 生成器表达式和列表推导式
- 生成器
- 内置函数
- itertools 模块
- The functools module
- Small functions and the lambda expression
- Revision History and Acknowledgements
- 引用文献
- 日志 HOWTO
- 日志基础教程
- 进阶日志教程
- 日志级别
- 有用的处理程序
- 记录日志中引发的异常
- 使用任意对象作为消息
- 优化
- 日志操作手册
- 在多个模块中使用日志
- 在多线程中使用日志
- 使用多个日志处理器和多种格式化
- 在多个地方记录日志
- 日志服务器配置示例
- 处理日志处理器的阻塞
- Sending and receiving logging events across a network
- Adding contextual information to your logging output
- Logging to a single file from multiple processes
- Using file rotation
- Use of alternative formatting styles
- Customizing LogRecord
- Subclassing QueueHandler - a ZeroMQ example
- Subclassing QueueListener - a ZeroMQ example
- An example dictionary-based configuration
- Using a rotator and namer to customize log rotation processing
- A more elaborate multiprocessing example
- Inserting a BOM into messages sent to a SysLogHandler
- Implementing structured logging
- Customizing handlers with dictConfig()
- Using particular formatting styles throughout your application
- Configuring filters with dictConfig()
- Customized exception formatting
- Speaking logging messages
- Buffering logging messages and outputting them conditionally
- Formatting times using UTC (GMT) via configuration
- Using a context manager for selective logging
- 正则表达式HOWTO
- 概述
- 简单模式
- 使用正则表达式
- 更多模式能力
- 修改字符串
- 常见问题
- 反馈
- 套接字编程指南
- 套接字
- 创建套接字
- 使用一个套接字
- 断开连接
- 非阻塞的套接字
- 排序指南
- 基本排序
- 关键函数
- Operator 模块函数
- 升序和降序
- 排序稳定性和排序复杂度
- 使用装饰-排序-去装饰的旧方法
- 使用 cmp 参数的旧方法
- 其它
- Unicode 指南
- Unicode 概述
- Python's Unicode Support
- Reading and Writing Unicode Data
- Acknowledgements
- 如何使用urllib包获取网络资源
- 概述
- Fetching URLs
- 处理异常
- info and geturl
- Openers and Handlers
- Basic Authentication
- Proxies
- Sockets and Layers
- 脚注
- Argparse 教程
- 概念
- 基础
- 位置参数介绍
- Introducing Optional arguments
- Combining Positional and Optional arguments
- Getting a little more advanced
- Conclusion
- ipaddress模块介绍
- 创建 Address/Network/Interface 对象
- 审查 Address/Network/Interface 对象
- Network 作为 Address 列表
- 比较
- 将IP地址与其他模块一起使用
- 实例创建失败时获取更多详细信息
- Argument Clinic How-To
- The Goals Of Argument Clinic
- Basic Concepts And Usage
- Converting Your First Function
- Advanced Topics
- 使用 DTrace 和 SystemTap 检测CPython
- Enabling the static markers
- Static DTrace probes
- Static SystemTap markers
- Available static markers
- SystemTap Tapsets
- 示例
- Python 常见问题
- Python常见问题
- 一般信息
- 现实世界中的 Python
- 编程常见问题
- 一般问题
- 核心语言
- 数字和字符串
- 性能
- 序列（元组/列表）
- 对象
- 模块
- 设计和历史常见问题
- 为什么Python使用缩进来分组语句？
- 为什么简单的算术运算得到奇怪的结果？
- 为什么浮点计算不准确？
- 为什么Python字符串是不可变的？
- 为什么必须在方法定义和调用中显式使用“self”？
- 为什么不能在表达式中赋值？
- 为什么Python对某些功能（例如list.index()）使用方法来实现，而其他功能（例如len(List)）使用函数实现？
- 为什么 join()是一个字符串方法而不是列表或元组方法？
- 异常有多快？
- 为什么Python中没有switch或case语句？
- 难道不能在解释器中模拟线程，而非得依赖特定于操作系统的线程实现吗？
- 为什么lambda表达式不能包含语句？
- 可以将Python编译为机器代码，C或其他语言吗？
- Python如何管理内存？
- 为什么CPython不使用更传统的垃圾回收方案？
- CPython退出时为什么不释放所有内存？
- 为什么有单独的元组和列表数据类型？
- 列表是如何在CPython中实现的？
- 字典是如何在CPython中实现的？
- 为什么字典key必须是不可变的？
- 为什么 list.sort() 没有返回排序列表？
- 如何在Python中指定和实施接口规范？
- 为什么没有goto？
- 为什么原始字符串（r-strings）不能以反斜杠结尾？
- 为什么Python没有属性赋值的“with”语句？
- 为什么 if/while/def/class语句需要冒号？
- 为什么Python在列表和元组的末尾允许使用逗号？
- 代码库和插件 FAQ
- 通用的代码库问题
- 通用任务
- 线程相关
- 输入输出
- 网络 / Internet 编程
- 数据库
- 数学和数字
- 扩展/嵌入常见问题
- 可以使用C语言中创建自己的函数吗？
- 可以使用C++语言中创建自己的函数吗？
- C很难写，有没有其他选择？
- 如何从C执行任意Python语句？
- 如何从C中评估任意Python表达式？
- 如何从Python对象中提取C的值？
- 如何使用Py_BuildValue()创建任意长度的元组？
- 如何从C调用对象的方法？
- 如何捕获PyErr_Print()（或打印到stdout / stderr的任何内容）的输出？
- 如何从C访问用Python编写的模块？
- 如何从Python接口到C ++对象？
- 我使用Setup文件添加了一个模块，为什么make失败了？
- 如何调试扩展？
- 我想在Linux系统上编译一个Python模块，但是缺少一些文件。为什么?
- 如何区分“输入不完整”和“输入无效”？
- 如何找到未定义的g++符号__builtin_new或__pure_virtual？
- 能否创建一个对象类，其中部分方法在C中实现，而其他方法在Python中实现（例如通过继承）？
- Python在Windows上的常见问题
- 我怎样在Windows下运行一个Python程序？
- 我怎么让 Python 脚本可执行？
- 为什么有时候 Python 程序会启动缓慢？
- 我怎样使用Python脚本制作可执行文件？
- *.pyd 文件和DLL文件相同吗？
- 我怎样将Python嵌入一个Windows程序？
- 如何让编辑器不要在我的 Python 源代码中插入 tab ？
- 如何在不阻塞的情况下检查按键？
- 图形用户界面（GUI）常见问题
- 图形界面常见问题
- Python 是否有平台无关的图形界面工具包？
- 有哪些Python的GUI工具是某个平台专用的？
- 有关Tkinter的问题
- “为什么我的电脑上安装了 Python ？”
- 什么是Python？
- 为什么我的电脑上安装了 Python ？
- 我能删除 Python 吗？
- 术语对照表
- 文档说明
- Python 文档贡献者
- 解决 Bug
- 文档错误
- 使用 Python 的错误追踪系统
- 开始为 Python 贡献您的知识
- 版权
- 历史和许可证
- 软件历史
- 访问Python或以其他方式使用Python的条款和条件
- Python 3.7.3 的 PSF 许可协议
- Python 2.0 的 BeOpen.com 许可协议
- Python 1.6.1 的 CNRI 许可协议
- Python 0.9.0 至 1.2 的 CWI 许可协议
- 集成软件的许可和认可
- Mersenne Twister
- 套接字
- Asynchronous socket services
- Cookie management
- Execution tracing
- UUencode and UUdecode functions
- XML Remote Procedure Calls
- test_epoll
- Select kqueue
- SipHash24
- strtod and dtoa
- OpenSSL
- expat
- libffi
- zlib
- cfuhash
- libmpdec