title: how can I write function with optional output parameters in python
body: <p>how can I write function with optional output parameters.
  In example</p>
  
  <p>1) <code>mat = ReadBinFile(filename)</code>
  or<br>
  2) <code>[mat,titles] = ReadBinFile(filename)</code></p>
  
  <p>if i finished the "ReadBinFile" function with </p>
  
  <pre><code>return mat,titles
  </code></pre>
  
  <p>i have a tuple in "mat" in the first example</p>
  
  <p>Thank You for the Help</p>