Can tell mypy just to test the module instead

.travis.yml

@@ -12,7 +12,7 @@ install:
   - pip install -r requirements.txt
   - pip install coveralls
 script:
-  - mypy basic_utils/*.py
+  - mypy basic_utils
   - coverage run --branch -m pytest && coverage report -m
   - python -m doctest basic_utils/[a-zA-Z]*.py
 after_success: