PyLint reports E0401 for relative imports

[rucker]

Example below. Issue is present in modules dfm env and ioutils

$ python3 -m pylint dfm.py
************* Module dfm
E0401: 10,0: : Unable to import 'env'
E0401: 11,0: : Unable to import 'ioutils'
E0401: 12,0: : Unable to import 'ioutils.ioutils'

...

Messages
--------

+-------------+------------+
|message id   |occurrences |
+=============+============+
|import-error |3           |
+-------------+------------+

[rucker]

Resolved in #54