The -m switch added in Python 2.4 to execute a module as a script gained a few more abilities. Instead of being implemented in C code inside the Python interpreter, the switch now uses an implementation in a new module, runpy.
The runpy module implements a more sophisticated import
mechanism so that it's now possible to run modules in a package such
as pychecker.checker. The module also supports alternative
import mechanisms such as the zipimport module. This means
you can add a .zip archive's path to
sys.path and then use the
-m switch to execute code from the archive.
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