title: Comprehensive list of Python protocols/interfaces
body: <p>Lately, I was looking at some Python idioms.
  I found many descriptions of protocols used in Python, such as the ordering (<code>__cmp__</code>, ...) or generators. Besides, there are also methods like <code>__hash__</code> which are defined for every object (I suppose).</p>
  
  <p>After some search on the internet, I haven't found a comprehensive list of these protocols and methods.
  Can anyone give me some <strike>pointers</strike> URLs?</p>