Write Docstrings

[fantix]

• [x] api.py
• [x] engine.py
• [x] crud.py
• [x] declarative.py
• [x] strategies.py
• [x] transaction.py
• [x] loader.py
• [x] aiocontextvars.py
• [ ] json_support.py
• [ ] exceptions.py
• [x] ext/__init__.py

Dialect related:

• [ ] dialects/__init__.py
• [ ] dialects/base.py
• [ ] dialects/asyncpg.py

Won't fix:

• [ ] schema.py

[thakkardharmik]

@fantix I would like to contribute to the project. Please guide.

[fantix]

@thakkardharmik Ah, much appreciated! Please reply with the file(s) you'd like to write docstring on and I'll mark your name on it so that someone else won't conflict you. After you're done please send a pull request. Besides there're also other issues marked as help wanted, similar process. Thanks in advance =)