title: How to check if a file is already opened (in the same process)
body: <p>And I'd like to specifically achieve that with the try catch construct.</p>
  
  <p>This <a href="https://stackoverflow.com/questions/6825994/check-if-a-file-is-open-in-python">related question</a> suggests that I can do:</p>
  
  <pre><code>try:
      open(fileName, 'wb+')
  except:
      print("File already opened!")
      raise
  </code></pre>
  
  <p>However, it doesn't work me. I can open the same file multiple times without any problem:</p>
  
  <pre><code>fileObj1 = open(fileName, 'wb+')
  fileObj2 = open(fileName, 'wb+')
  </code></pre>
  
  <p>Is it because I have Python 3.5? Or because I'm using <a href="https://www.raspberrypi.org/downloads/raspbian/" rel="noreferrer">Raspbian</a>?</p>
  
  <p>Thanks for the help!</p>