I am working on a project with following tree structure: Project app main.py svg_to_png.py __init__.py tests __init__.py unittests basic_test.py __init__.py I am importing app functions to basic_tests by using from app.main import * when I execute the basic_test.py, it gives the following error: ImportError: No module named 'app' Also, while in the top directory of the project, when I type python3 -m app.main, the program executes for a while, then gives the same import error at the following line from app.svg_to_png import do_svg2png Continue reading...