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, 2 insertions, 2 deletions

diff --git a/lib/sqlalchemy/dialects/postgresql/psycopg2.py b/lib/sqlalchemy/dialects/postgresql/psycopg2.py
index 0bbad3257..d670d1a50 100644
--- a/lib/sqlalchemy/dialects/postgresql/psycopg2.py
+++ b/lib/sqlalchemy/dialects/postgresql/psycopg2.py
@@ -558,7 +558,7 @@ class PGDialect_psycopg2(_PGDialect_common_psycopg):
         executemany_mode="values_only",
         executemany_batch_page_size=100,
         executemany_values_page_size=1000,
-        **kwargs
+        **kwargs,
     ):
         _PGDialect_common_psycopg.__init__(self, **kwargs)
 
@@ -737,7 +737,7 @@ class PGDialect_psycopg2(_PGDialect_common_psycopg):
                 parameters,
                 template=executemany_values,
                 fetch=bool(context.compiled.returning),
-                **kwargs
+                **kwargs,
             )
 
         elif self.executemany_mode & EXECUTEMANY_BATCH: