As Paolo said, we have 2 invocation methods:

1) python -m tests.core_test 2) python tests/core_test.py 

One difference between them is sys.path[0] string. Since the interpret will search sys.path when doing import, we can do with tests/core_test.py:

if __name__ == '__main__': import sys from pathlib import Path sys.path.insert(0, str(Path(__file__).resolve().parent.parent)) from components import core <other stuff> 

And more after this, we can run core_test.py with other methods:

cd tests python core_test.py python -m core_test ... 

Note, py36 tested only.

As Paolo said, we have two invocation methods:

1. python -m tests.core_test
2. python tests/core_test.py

One difference between them is the sys.path[0] string. Since the interpret will search sys.path when doing import, we can do with tests/core_test.py:

if __name__ == '__main__': import sys from pathlib import Path sys.path.insert(0, str(Path(__file__).resolve().parent.parent)) from components import core <other stuff> 

And more after this, we can run core_test.py with other methods:

cd tests python core_test.py python -m core_test ... 

Note, tested only on Python 3.6.