Added explanations for zip(), filter() and map()

[LAbhilashKumar]

Added Examples and Explanations for Python’s Built-in Generator Functions

Included a brief overview of zip(), map(), and filter() functions in the about.md file.

Explained how each function works, along with simple examples to demonstrate their usage in Python.

zip() combines iterables, map() applies a function to each item in an iterable, and filter() filters items based on a given condition.
Addresses feature: #3532

[github-actions]

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