title: Get built in method signature - Python
body: <p>How do I get the signature of built in methods?
  Example: dict().get(k)</p>
  
  <pre><code>&gt;&gt; a = dict().get
  &gt;&gt; a
  &lt;built-in method get of dict object at 0x1003aafd0&gt;
  &gt;&gt; a.__doc__
  'D.get(k[,d]) -&gt; D[k] if k in D, else d.  d defaults to None.'
  &gt;&gt; import inspect
  &gt;&gt; inspect.getargspec(a)
  TypeError: &lt;built-in method get of dict object at 0x100377250&gt; is not a Python function
  </code></pre>
  
  <p>I would like to see the result like this</p>
  
  <pre><code>&gt;&gt; a.some_function()
  ('key', 'default'=None)
  </code></pre>