Can I import a file without file extension .py?

[Jia Lu]

>
>     def make_module_from_file(module_name, file_name):
>         """ Make a new module object from the code in specified file """
>
>         from types import ModuleType
>         module = ModuleType(module_name)
>
>         module_file = open(file_name, 'r')
>         exec module_file in module.__dict__

Thank you very much.
And can you tell me what does " exec module_file in module.__dict__ "
mean?

Thanx