Bump min python to 3.10, so TypeAlias works

Author: ksunden

.github/workflows/testing.yml

@@ -8,7 +8,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        python-version: ["3.9", "3.10"]
+        python-version: ["3.10", "3.11", "3.12"]
       fail-fast: false
 
     steps:

setup.py

@@ -6,7 +6,7 @@
 # NOTE: This file must remain Python 2 compatible for the foreseeable future,
 # to ensure that we error out properly for people with outdated setuptools
 # and/or pip.
-min_version = (3, 9)
+min_version = (3, 10)
 if sys.version_info < min_version:
     error = """
 data_prototype does not support Python {0}.{1}.