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, 4 insertions, 4 deletions

diff --git a/test/dialect/postgresql/test_dialect.py b/test/dialect/postgresql/test_dialect.py
index 02d7ad483..cd6c127b8 100644
--- a/test/dialect/postgresql/test_dialect.py
+++ b/test/dialect/postgresql/test_dialect.py
@@ -374,7 +374,7 @@ class ExecuteManyMode:
                         {"x": "x2", "y": "y2"},
                         {"x": "x3", "y": "y3"},
                     ),
-                    **expected_kwargs
+                    **expected_kwargs,
                 )
             ],
         )
@@ -423,7 +423,7 @@ class ExecuteManyMode:
                         {"x": "x2", "y": "y2"},
                         {"x": "x3", "y": "y3"},
                     ),
-                    **expected_kwargs
+                    **expected_kwargs,
                 )
             ],
         )
@@ -476,7 +476,7 @@ class ExecuteManyMode:
                         {"x": "x2", "y": "y2"},
                         {"x": "x3", "y": "y3"},
                     ),
-                    **expected_kwargs
+                    **expected_kwargs,
                 )
             ],
         )
@@ -529,7 +529,7 @@ class ExecuteManyMode:
                             {"xval": "x1", "yval": "y5"},
                             {"xval": "x3", "yval": "y6"},
                         ),
-                        **expected_kwargs
+                        **expected_kwargs,
                     )
                 ],
             )