The patch adds this check:

+	    if not filename.endswith((".pyc", ".pyo", ".py")):
+                continue

This is not valid. A Python file is a text file with python code. In spite of import conventions, they are not required to have any particular extension and some people omit them from main scripts. Trace works fine with such files now and your patch would prevent that. Python files are only identified as such by trying to parse them.

The problem and solution lie with your setup. Arrange things so Bitten only treats Python files as Python files.