pdfminer package: module isn't found

[Pavel_47]

I am using pdfminer 20191125 with Python 3.9.0.
What does this print?

import pkgutil, pdfminer
for a, modname, c in pkgutil.walk_packages(path=pdfminer.__path__):
    print(modname)

Output:
>>> import pkgutil, pdfminer
>>> for a, modname, c in pkgutil.walk_packages(path=pdfminer.__path__):
	    print(modname)

	    
rijndael
>>>