title: Pycharm import does not recognize other files in the same module
body: <p>Say, my project structure is as following:</p>
  
  <pre><code>project_folder:
    __init__.py
    another_folder:
      __init__.py
      main_file.py
      other_file.py
  </code></pre>
  
  <p>And <code>main_file.py</code> contains next code:</p>
  
  <pre><code>import other_file as whatever
  </code></pre>
  
  <p>PyCharm (PEP8) highlights this line as an error '<code>no module named other_file</code>' and there is no autocomplete on any calls like <code>whatever.this_should_be_autoc_suggested</code>. Meanwhile interpreter works perfectly fine. </p>
  
  <p>What can be the cause of this annoying behaviour?</p>