#### 定义变量 ``` num = 10 print(type(num)) #<class 'int'> 数据类型 print(id(num)) #506323872 内存地址 ``` #### 删除变量 ``` num = 1 del num print(type(num)) //报错，删除后不能再用 ``` #### 连续赋值 ``` num1 = num2 = 3 print(num1, num2) ``` #### 交互赋值 ``` num1, num2, num3 = 1,2,3 print(num1, num2, num3) ``` #### None ``` num = 10 num = None print(num) #None print(type(None)) #<class 'NoneType'> ```