title: How do I store a db.Blob in Google App Engine's blobstore?
body: <p>In a python Google App engine app, I can create a <code>db.Blob</code> object containing binary data:</p>
  
  <pre><code>blob = db.Blob(open("image.png", "rb").read())
  </code></pre>
  
  <p>How do I store that as the value of a <code>blobstore.BlobReferenceProperty</code>?</p>
  
  <p>I could create a URL handle and send the blob across a URL, but can I somehow turn the <code>db.Blob</code> into a blob store entity directly?</p>