title: Upload local files using Google Colab
body: <p>Trying to upload local files using Google Collaboratory this way:</p>
  
  <pre><code>from google.colab import files
  uploaded = files.upload()
  </code></pre>
  
  <p>I get the following error:</p>
  
  <blockquote>
    <p>Upload widget is only available when the cell has been executed in the current browser session. Please rerun this cell to enable.</p>
  </blockquote>
  
  <p>I rerun the cell but it doesn't work...</p>