extracting dictionary pairs based on value
<p>I want to copy pairs from this dictionary based on their <em>values</em> so they can be assigned to new variables. From my research it seems easy to do  <a href="http://stackoverflow.com/questions/5352546/best-way-to-extract-subset-of-key-value-pairs-from-python-dictionary-object">this</a> based on keys, but in my case the values are what I'm tracking.</p>

<pre>
things = ({'alpha': 1, 'beta': 2, 'cheese': 3, 'delta': 4})
</pre>

<p>And in made-up language I can assign variables like so -</p>

<pre><code>smaller_things =  all values =3 in things 
</code></pre>
