Update Black's target-version to py37

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### Description
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Black's `target-version` was still set to `['py27', 'py36']`. Set it to `[py37]` instead.

Also update Black and other pre-commit hooks and re-format with Black.

### Checklist
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This pull request is:

- [ ] A documentation / typographical error fix
	- Good to go, no issue or tests are needed
- [ ] 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: #7536
Pull-request: https://github.com/sqlalchemy/sqlalchemy/pull/7536
Pull-request-sha: b3aedf5570d7e0ba6c354e5989835260d0591b08

Change-Id: I8be85636fd2c9449b07a8626050c8bd35bd119d5

1 files changed, 5 insertions, 5 deletions

diff --git a/lib/sqlalchemy/sql/coercions.py b/lib/sqlalchemy/sql/coercions.py
index 1a0336c67..d11ab6712 100644
--- a/lib/sqlalchemy/sql/coercions.py
+++ b/lib/sqlalchemy/sql/coercions.py
@@ -115,7 +115,7 @@ def expect(
     apply_propagate_attrs=None,
     argname=None,
     post_inspect=False,
-    **kw
+    **kw,
 ):
     if (
         role.allows_lambda
@@ -205,7 +205,7 @@ def expect(
                 resolved,
                 argname=argname,
                 original_element=original_element,
-                **kw
+                **kw,
             )
         return resolved
     else:
@@ -441,7 +441,7 @@ class _SelectIsNotFrom:
             resolved=resolved,
             advice=advice,
             code=code,
-            **kw
+            **kw,
         )
 
 
@@ -956,7 +956,7 @@ class FromClauseImpl(_SelectIsNotFrom, _NoTextCoercion, RoleImpl):
         argname=None,
         explicit_subquery=False,
         allow_select=True,
-        **kw
+        **kw,
     ):
         if resolved._is_select_statement:
             if explicit_subquery:
@@ -991,7 +991,7 @@ class StrictFromClauseImpl(FromClauseImpl):
         resolved,
         argname=None,
         allow_select=False,
-        **kw
+        **kw,
     ):
         if resolved._is_select_statement and allow_select:
             util.warn_deprecated(