Fix part of #13341: Added Mypy type annotations to the script directory's root level files.

[sahiljoster32]

Overview

1. This PR fixes or fixes part of Add type annotations to files of scripts folder #13341.
2. This PR does the following: This PR adds MyPy type annotations to the root-level files of the script directory.

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[oppiabot]

Hi @sahiljoster32. Due to recent changes in the "develop" branch, this PR now has a merge conflict. Please follow this link if you need help resolving the conflict, so that the PR can be merged. Thanks!

[aasiffaizal]

LGTM

[oppiabot]

Unassigning @aasiffaizal since they have already approved the PR.

[sahiljoster32]

@U8NWXD PTAL!

[sahiljoster32]

@U8NWXD PTAL!

[oppiabot]

Hi @sahiljoster32, there is a new change in develop which needs to be in your PR. Please update your branch with the latest changes in develop. For instructions, refer to this link. Thanks!

[oppiabot]

Hi @sahiljoster32, this PR is ready to be merged. Please address any remaining comments prior to merging, and feel free to merge this PR once the CI checks pass and you're happy with it. Thanks!