Some branches of the decision tree in the search algorithm rely on having a location for the user. That location can be determined in several ways:

• Supplied as a URL parameter, _location
• Derived from the originating request's IP address
• Supplied from some additional, arbitrary source in code

And may be expressed in several different formats:

• As a comma separated string of latitude and longitude float values
• As a string in Well Known Text format
• As a string in Extended Well Known Text format
• As a 2-tuple of latitude and longitude
• As a 3-tuple of latitude, longitude, and spatial reference id

It will be useful and more maintainable if most of our code has a known object type it can rely on, that parses and normalizes the various inbound sources/formats during instantiation.