Django's @cached_property decorator is very useful for implementing

properties that call expensive methods, as it takes care of all the

caching. Unfortunately, it doesn't behave like a standard property. It

overwrites the documentation and does not retain the name and

attributes. Introspecting the property (such as for documentation

generation purposes) results in some bad information.
This introduces a smarter version of @cached_property. It's a drop-in

replacement that retains the documentation and attributes, like a normal

decorator would.
Unit tests were added to ensure it works correctly, and existing call

sites were updated to use it.

Unit tests pass.
Built some docs and saw that the doc string from the method wrapped by

@cached_property was showing up instead of the one on

@cached_property itself.