The doc command for os.mkdir is incorrect (at least for posix). It specifies that there is an optional mode keyword, but it's not a keyword argument, see below:

>>> import os
>>> help(os.mkdir)
mkdir(...)
    mkdir(path [, mode=0777])
    
    Create a directory.

>>> os.mkdir("/tmp/1", mode=777) 
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
TypeError: mkdir() takes no keyword arguments


Suggest the following doc comment change:

mkdir(...)
    mkdir(path [, mode])
    
    Create a directory. Mode defaults to 0777 if not specified.