title: Python module for storing and querying geographical coordinates
body: <p>Is there a Python module where I can create objects with a geographical location coordinate (latitude and longitude), and query all the objects for ones which are within a 5km distance (i.e. radius) of a given coordinate?</p>
  
  <p>I've been trying to store the latitude and longitude as keys in dictionaries (as they're indexed by key) and use some distance finding algorithms to query them. But this feels like a horrible hack.</p>
  
  <p>Essentially something like PostGIS for PostgreSQL, but all within my Python app's memory.</p>