理解Python -m mod : run library module as a script

• -m

  from python -h, -m mod : run library module as a script (terminates option list).

  Python modules are just script files that are located in a place where Python can find them.

  As with all scripts, you can just run them directly if you know where they are, e.g. python /path/to/module.py

• __name__ in Python

  As we learn from What does if __name__ == “__main__”: do? ,a .py file can be executed in two ways:

  1. as main program
  2. imported by another

• run library module as a script

  If you want run a module as main program, you should know the full path to the module ,like python /path/module.py, also can use the python -m module just get the same result.

  直接执行的是module.py脚本，通过-m参数是执行module实现执行module.py的效果。