Remove redundant code for EOL Python <= 3.6

<!-- Provide a general summary of your proposed changes in the Title field above -->

### Description
<!-- Describe your changes in detail -->

There's a few bits and pieces of code to support Python <= 3.6 which are no longer needed and can be removed, to slightly simplify the codebase.

### Checklist
<!-- go over following points. check them with an `x` if they do apply, (they turn into clickable checkboxes once the PR is submitted, so no need to do everything at once)

-->

This pull request is:

- [ ] A documentation / typographical error fix
	- Good to go, no issue or tests are needed
- [x] A short code fix
	- please include the issue number, and create an issue if none exists, which
	  must include a complete example of the issue.  one line code fixes without an
	  issue and demonstration will not be accepted.
	- Please include: `Fixes: #<issue number>` in the commit message
	- please include tests.   one line code fixes without tests will not be accepted.
- [ ] A new feature implementation
	- please include the issue number, and create an issue if none exists, which must
	  include a complete example of how the feature would look.
	- Please include: `Fixes: #<issue number>` in the commit message
	- please include tests.

**Have a nice day!**

Closes: #7544
Pull-request: https://github.com/sqlalchemy/sqlalchemy/pull/7544
Pull-request-sha: 282b4a91282902a57807aa2541b75b272b547127

Change-Id: I9ddf15fcf72551d52e3f027f337c7fee4aa9083b

1 files changed, 2 insertions, 4 deletions

diff --git a/lib/sqlalchemy/sql/lambdas.py b/lib/sqlalchemy/sql/lambdas.py
index b2c366671..8af727bbe 100644
--- a/lib/sqlalchemy/sql/lambdas.py
+++ b/lib/sqlalchemy/sql/lambdas.py
@@ -8,7 +8,6 @@
 import collections.abc as collections_abc
 import itertools
 import operator
-import sys
 import types
 import weakref
 
@@ -1113,9 +1112,8 @@ class AnalyzedFunction:
         func = type(f)(
             f.__code__, globals_, f.__name__, f.__defaults__, closure
         )
-        if sys.version_info >= (3,):
-            func.__annotations__ = f.__annotations__
-            func.__kwdefaults__ = f.__kwdefaults__
+        func.__annotations__ = f.__annotations__
+        func.__kwdefaults__ = f.__kwdefaults__
         func.__doc__ = f.__doc__
         func.__module__ = f.__module__