imported modules becomes None when replacing current module in sys.modules using a class object

Question

an unpopular but \"supported\" python hack (see Guido: https://mail.python.org/pipermail/python-ideas/2012-May/014969.html) that enables __getattr__ usage on mo

Answer 1

The problem you are running in to is that in Pythons prior to 3.4 when a module is destroyed (as yours is because you replace it with a class and there are no further references to it), the items in that module's __dict__ are forcibly set to None.

The workaround, if you need to support Pythons prior to 3.4, is have an import statement in the class that will replace the module:

class MyClass(object):

    import os

    def check_os(self):
        print(os)

For more info, see this answer about interpreter shutdown.