Fix anti-patterns

[tusharnankani]

Describe the changes you've made

This PR fixes antipatterns:

• Remove unused imported modules to optimize performance
• Open files using with
  • Opening a file using with statement is preferred as function open implements the context manager protocol that releases the resource when it is outside of the with block. Not doing so requires you to manually release the resource.

Describe if there is any unusual behaviour of your code(Write NA if there isn't)

NA

Checklist

• [X] My code follows the code style of this project.
• [X] I have performed a self-review of my own code.
• [ ] My change requires a change to the documentation.
• [ ] I have updated the documentation accordingly.
• [X] I have read the CONTRIBUTING document.
• [X] I have commented my code, particularly in hard-to-understand areas.
• [X] My changes generate no new warnings.
• [X] I have added tests that prove my fix is effective or that my feature works.
• [X] The title of my pull request is a short description of the requested changes.

[welcome[bot]]

Hello there!👋 Welcome to the alphadoc!

Thank you and congrats🎉 for opening your first pull request. We will get back to you as soon as we can 😄.

[welcome[bot]]

Congrats on merging your first pull request! 🎉 All the best for your amazing open source journey ahead 🚀.

[tusharnankani]

Does this come under any DWOC level? @V2dha

[tusharnankani]

And what about this @V2dha

[V2dha]

And what about this @V2dha

Sorry forgot about this one! I'll add the labels.

[V2dha]

Thank you for your contributions!