title: Python3 append value to array but only if it's not None
body: <p>I got function that it's searching for something, and may not return anything.
  I want to append it to array but only if it return something</p>
  
  <p>pseudocode</p>
  
  <pre><code>def fu():
      if sometring:
          return result
  
  a = []
  a.append(fu())
  </code></pre>
  
  <p>now if this function doesn't return value it appends "None" to array <code>[result1, None, result2,etc]</code>, how to avoid that?</p>