feat(spanner): drop support for python 3.9

Author: chalmerlowe

packages/google-cloud-spanner/README.rst

@@ -62,14 +62,14 @@ Supported Python Versions
 Our client libraries are compatible with all current `active`_ and `maintenance`_ versions of
 Python.
 
-Python >= 3.9, including 3.14
+Python >= 3.10, including 3.14
 
 .. _active: https://devguide.python.org/devcycle/#in-development-main-branch
 .. _maintenance: https://devguide.python.org/devcycle/#maintenance-branches
 
 Unsupported Python Versions
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^
-Python <= 3.8
+Python <= 3.9
 
 If you are using an `end-of-life`_
 version of Python, we recommend that you update as soon as possible to an actively supported version.

packages/google-cloud-spanner/docs/README.rst

@@ -62,14 +62,14 @@ Supported Python Versions
 Our client libraries are compatible with all current `active`_ and `maintenance`_ versions of
 Python.
 
-Python >= 3.9, including 3.14
+Python >= 3.10, including 3.14
 
 .. _active: https://devguide.python.org/devcycle/#in-development-main-branch
 .. _maintenance: https://devguide.python.org/devcycle/#maintenance-branches
 
 Unsupported Python Versions
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^
-Python <= 3.8
+Python <= 3.9
 
 If you are using an `end-of-life`_
 version of Python, we recommend that you update as soon as possible to an actively supported version.

packages/google-cloud-spanner/noxfile.py

@@ -31,7 +31,6 @@
 SYSTEM_TEST_PYTHON_VERSIONS: List[str] = ["3.12"]
 
 ALL_PYTHON: List[str] = [
-    "3.9",
     "3.10",
     "3.11",
     "3.12",

packages/google-cloud-spanner/setup.py

@@ -86,7 +86,6 @@
         "License :: OSI Approved :: Apache Software License",
         "Programming Language :: Python",
         "Programming Language :: Python :: 3",
-        "Programming Language :: Python :: 3.9",
         "Programming Language :: Python :: 3.10",
         "Programming Language :: Python :: 3.11",
         "Programming Language :: Python :: 3.12",
@@ -97,7 +96,7 @@
     ],
     platforms="Posix; MacOS X; Windows",
     packages=packages,
-    python_requires=">=3.9",
+    python_requires=">=3.10",
     install_requires=dependencies,
     extras_require=extras,
     include_package_data=True,

packages/google-cloud-spanner/testing/constraints-3.9.txt

@@ -2783,9 +2783,7 @@ async def test_list_sessions_async_pages():
             RuntimeError,
         )
         pages = []
-        # Workaround issue in python 3.9 related to code coverage by adding `# pragma: no branch`
-        # See https://github.com/googleapis/gapic-generator-python/pull/1174#issuecomment-1025132372
-        async for page_ in (  # pragma: no branch
+        async for page_ in (
             await client.list_sessions(request={})
         ).pages:
             pages.append(page_)