Remove mention of Python 3.6 from README (#67)

MoshiBin · hauntsaninja · web-flow · commit 3a61a949c3e9 · 2022-09-05T18:29:37.000-07:00
Co-authored-by: Shantanu &lt;12621235+hauntsaninja@users.noreply.github.com&gt;
diff --git a/README.md b/README.md
@@ -8,7 +8,7 @@ The `typing_extensions` module serves two related purposes:
 
 - Enable use of new type system features on older Python versions. For example,
   `typing.TypeGuard` is new in Python 3.10, but `typing_extensions` allows
-  users on Python 3.6 through 3.9 to use it too.
+  users on previous Python versions to use it too.
 - Enable experimentation with new type system PEPs before they are accepted and
   added to the `typing` module.
 
