Log Message:
3.13.0:

This release has two major aspects to it: The first is the introduction of \ 
:func:`~hypothesis.strategies.deferred`, which allows more natural definition of \ 
recursive (including mutually recursive) strategies.

The second is a number of engine changes designed to support this sort of \ 
strategy better. These should have a knock-on effect of also improving the \ 
performance of any existing strategies that currently generate a lot of data or \ 
involve heavy nesting by reducing their typical example size.