Add docstrings and replace dict|List with dict|list

[rnetser]

Description

How Has This Been Tested?

Merge criteria:

• The commits are squashed in a cohesive manner and have meaningful messages.
• Testing instructions have been added in the PR body (for PRs involving changes that are not immediately obvious).
• The developer has manually tested the changes and verified that the changes work

[github-actions]

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• Run pre-commit
• Run tox

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