<s>[INST] Python: import a file from a subdirectory I have a file called tester.py, located on /project.
/project has a subdirectory called lib, with a file called BoxTime.py:
/project/tester.py
/project/lib/BoxTime.py

I want to import BoxTime from tester. I have tried this:
import lib.BoxTime

Which resulted:
Traceback (most recent call last):
  File "./tester.py", line 3, in <module>
    import lib.BoxTime
ImportError: No module named lib.BoxTime

Any ideas how to import BoxTime from the subdirectory?
EDIT
The __init__.py was the problem, but don't forget to refer to BoxTime as lib.BoxTime, or use:
import lib.BoxTime as BT
...
BT.bt_function()

 [/INST] Take a look at the Packages documentation (Section 6.4) here: http://docs.python.org/tutorial/modules.html
In short, you need to put a blank file named 
__init__.py

in the "lib" directory.
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