Importing from filesystem path a 'frozen sub-module' error

[Calvin Spealman]

I've been working on a small test runner script, to accumulate my test
scripts (all python files in the 'test' sub-directories of my source tree).
Things were going well, but I'm still having trouble loading the modules,
once I have a path to the python source file. This is the error I am
getting:

mod_info = imp.find_module(module_name, module_path)
ImportError: No frozen submodule named PyInvolgo.test.test_RepoBase

I know 100% sure the module exists (I can enter a python shell and import it
directly, no problem), so that isn't the problem. I don't know what a
'frozen sub-module' is, tho, and I haven't been able to find anything about
them from google searches and documentation on python.org.

At first, I thought maybe it was because the test directory had no
__init__.py (it isn't a package, so I didn't make one), but added one made
no difference.
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