def datacenters(self):
        """
        ::
        
            GET /:login/datacenters
        
        :Returns: all datacenters (mapping from short location key to 
            full URL) that this cloud is aware of
        :rtype: :py:class:`dict`
        
        This method also updates the local `known_locations` attribute based 
        upon this information.
        """
        j, _ = self.request('GET', '/datacenters')
        self.known_locations.update(j)
        return j