Add black

[vanessa]

Description

• Add black to project (along with configs in pyproject.toml)
• Format files in backend folder
• Add black to pre-commit hook
• Fix has_missing_migrations on pre-commit hook configs
• Add generated requirements files (.txt) to .gitignore

Note: Ignoring .py files in "Files changed" section removes the formatted files and cleans the diff a little bit, here's a shortcut

Motivation and Context

Closes #200

Steps to reproduce (if appropriate):

black

1. Clone the project as a user following these steps
2. After you compile and install requirements, check if black is installed by typing black
   • [ ] The output is No Path provided. Nothing to do 😴
3. Install pre-commit hook with pre-commit install
4. Create an example Python file inside backend folder
   • Use the example in black playground
5. Add the same file created previously inside a migrations folder (users/migrations for example)
6. Try to commit the file you created (or run pre-commit)
   • [ ] pre-commit hook runs and formats the file
   • [ ] The limit of 100 characters per line is respected
   • [ ] The file in migrations folder wasn't touched

has_missing_migrations on pre-commit

1. Run pre-commit
   • [ ] missing-migrations-local runs without problems

generated requirements files

1. Try to commit when you finish following steps in black section
   • [ ] The generated requirements.txt and dev-requirements.txt isn't included

Types of changes

• [x] Bug fix (non-breaking change which fixes an issue)
• [x] New feature (non-breaking change which adds functionality)
• [ ] Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• [x] My code follows the code style of this project.
• [x] My change requires documentation updates.
• [x] I have updated the documentation accordingly.
• [x] My change requires dependencies updates.
• [x] I have updated the dependencies accordingly.

[chocoelho]

Please, merge isort.cfg with the following configuration as suggested by Black, remove the duplicates and make the suggestions by Black supersed ours.:

[settings]
multi_line_output=3
include_trailing_comma=True
force_grid_wrap=0
use_parentheses=True

[vanessa]

@chocoelho Added them if you want to check :+1: