title: Size of pickled object wrt GAE BlobProperty
body: <p>I'm pickling a python dictonary, and storing it to a GAE BlobProperty. 
  The BlobProperty has a <a href="https://developers.google.com/appengine/docs/python/datastore/datamodeling?csw=1#Strings_Long_Strings_and_Blobs" rel="nofollow">1MB size limit</a>. I want to programmatically check that my object will 'fit' in that 1MB limit</p>
  
  <pre><code>import pickle
  p = pickle.dumps(some_object)
  print len(p)
  &gt;&gt;&gt;42000
  </code></pre>
  
  <p>But what is len(pickled_object) measuring? (the number of characters?), and how do I convert that to bytes, to check against the 1MB limit? I cant find the info on how the data in encoded to be able to compare the len() to the 1MB (e.g. bytes per 'character')</p>
  
  <p>thanks</p>