title: Read/Open image from instance of Python io.BufferedReader class
body: <p>I'm struggling to properly open a TIFF image from an instance of Python's <code>io.BufferedReader</code> class.  I download the image from a GCS path using the below lib, but I can't open seem to open the image with traditional tools.</p>
  
  <pre><code># returns the &lt;_io.BufferedReader&gt;
  file = beam.io.gcp.gcsio.GcsIO().open("&lt;GCS_PATH&gt;", 'r')
  
  from PIL import Image    
  img = Image.open(file.read()) &lt;---- Fails with "TypeError: embedded NUL character"
  
  img = Image.open(file.raw) &lt;--- Fails when any operations are performed with "IOError(err)"
  </code></pre>
  
  <p>I am open to other libraries besides PIL.</p>
  
  <p><strong>UPDATE</strong></p>
  
  <p>The following also fails:</p>
  
  <pre><code>img = Image.open(file)
  </code></pre>
  
  <p>It fails with an IOError, stating <code>tempfile.tif: Cannot read TIFF header.</code></p>