- update to 0.3.1:
* Hypothesis >= 6.89.0 made some internal changes which broke
our `from_grammar()`. This patch restores compatibility, and
requires the new Hypothesis.

- Update to version 0.2.3
* Use importlib.resources to load the Python grammar (zip-safe)
* Drop support for Python 3.6, add 3.10 and 3.11 to CI
Fixed rare internal error when from_node() generated misplaced except: clauses
* Fix internal error in `from_grammar("single_input")
* Emit more debug info to diagnose a compile() issue in CPython