What could cause a python module to be imported twice?

Solution 1:

A Python module can be imported twice if the module is found twice in the path. For example, say your project is laid out like so:

• src/
  • package1/
    • spam.py
    • eggs.py

Suppose your PYTHONPATH (sys.path) includes src and src/package1:

PYTHONPATH=/path/to/src:/path/to/src/package1

If that's the case, you can import the same module twice like this:

from package1 import spam
import spam

And Python will think they are different modules. Is that what's going on?

Also, per the discussion below (for users searching this question), another way a module can be imported twice is if there is an exception midway through the first import. For example, if spam imports eggs, but importing eggs results in an exception inside the module, it can be imported again.