pyday10&11&12-Common modules: time|datetime|os|sys|pickle|json|xml, string formatting, py auto Global variables

1. py file automatically created global variables

Print (VARs ()) return value: {' __name__ ': ' __main__ ', ' __package__ ': None, ' __loader__ ': <_frozen_importlib_external. Sourcefileloader object at 0x0000025471756e10>, ' __cached__ ': None, ' __doc__ ': None, ' __file__ ': ' c:/users/john/ pycharmprojects/q1/day12/index.py ', ' __spec__ ': None, ' __builtins__ ': <module ' builtins ' (built-in);}

1.1 Common variables:

__doc__ #py文件的注释
__file__# own path
__package__# the package where the current. PY is located
__cached __#py Cache
__name__# display the name of the py file;

1.2 Infrequently used variables:

__LOADER__: System call
__spec__ system Call
__builtins__# #存放内置函数

2. Module

For a complex function, multiple functions may be required to complete (functions can also be in different. py files), and the Code collection consisting of N. py files is called a module.

Like functional programming and process-oriented programming, functional programming accomplishes a function, and other code is used to invoke it, providing reusability of code and coupling between the code.

Modules can be divided into three types:

• Custom modules:
• Third-party modules:
• Built-in modules: Call directly

3.

4. End

pyday10&11&12-Common modules: time|datetime|os|sys|pickle|json|xml, string formatting, py auto Global variables