Custom component error in logs

I have the custom component set up and if recently started to log this error:
2019-03-21 14:47:46 WARNING (MainThread) [homeassistant.loader] Integrations need to be in their own folder. Change sensor/ to filesize/ This will stop working soon.

So, I have tried moving it (I think) as suggested and now I get this error:

2019-03-21 14:37:18 WARNING (MainThread) [homeassistant.loader] You are using a custom component for filesize which has not been tested by Home Assistant. This component might cause stability problems, be sure to disable it if you do experience issues with Home Assistant.
2019-03-21 14:37:18 ERROR (MainThread) [homeassistant.loader] Error loading custom_components.filesize.sensor. Make sure all dependencies are installed
Traceback (most recent call last):
  File "/usr/local/lib/python3.7/site-packages/homeassistant/", line 166, in _load_file
    module = importlib.import_module(path)
  File "/usr/local/lib/python3.7/importlib/", line 127, in import_module
    return _bootstrap._gcd_import(name[level:], package, level)
  File "<frozen importlib._bootstrap>", line 1006, in _gcd_import
  File "<frozen importlib._bootstrap>", line 983, in _find_and_load
  File "<frozen importlib._bootstrap>", line 962, in _find_and_load_unlocked
ModuleNotFoundError: No module named 'custom_components.filesize.sensor'; 'custom_components.filesize' is not a package

In the log file.

What am I doing wrong?