build/pkgs/typing_extensions: skip with python >= 3.11

Author: orlitzky

build/pkgs/typing_extensions/spkg-configure.m4

@@ -1,3 +1,24 @@
 SAGE_SPKG_CONFIGURE([typing_extensions],[
   SAGE_PYTHON_PACKAGE_CHECK([typing_extensions])
+],[
+  # Three of our python packages are backport packages providing
+  # python-3.11 features (see coding_in_python.rst):
+  #
+  #   * importlib_metadata
+  #   * importlib_resources
+  #   * typing_extensions
+  #
+  # These packages are therefore not needed with >=python-3.11. Here
+  # we test for a python minor version component greater than or equal
+  # to 11, and mark this package as "not required" if we succeed.
+  AC_MSG_CHECKING([for >=python-3.11])
+
+  # Keep in mind that False (~ zero) in python is success in the shell
+  AS_IF(["${PYTHON_FOR_VENV}" -c "import sys; sys.exit(sys.version_info.minor < 11)"],[
+    AC_MSG_RESULT([yes])
+    sage_require_typing_extensions="no"
+  ],[
+    AC_MSG_RESULT([no])
+  ])
 ])
+