Refactor getter functions

[mostafa]

Ticket(s)

• Refactor getter functions for time.Duration into a single reusable function #373

Description

This PR refactors and replaces getter functions for time.Duration and maps using generics.

Related PRs

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Development Checklist

• I have added a descriptive title to this PR.
• I have squashed related commits together.
• I have rebased my branch on top of the latest main branch.
• I have performed a self-review of my own code.
• I have commented on my code, particularly in hard-to-understand areas.
• I have added docstring(s) and type annotations to my code.
• I have made corresponding changes to the documentation (docs).
• I have added tests for my changes.

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