stash install moviepy

[zm]

everything is fine untill this very last of the log

Extracting archive file ...
Archive extracted.
Running setup file ...
ModuleNotFoundError("No module named 'ez_setup'",)
Failed to run setup.py
Fall back to directory guessing ...
Package installed: proglog

If I ignore this, actually I can

import moviepy

successfully.
BUT if I import any submodule of moviepy, there is always annoying AttributeError

'NoneType ' object has no attribute 'startswith'

I look into it, the problem is at _utils.py:

plat = get_platform()

plat will be None.
so

if plat.startswith("win"):

throws out

'NoneType ' object has no attribute 'startswith'