Create ipv4_conversion.py (#11008)

* Create ipconversion.py

* [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

* Update conversions/ipconversion.py

* Update ipconversion.py

* Rename ipconversion.py to ipv4_conversion.py

* forward_propagation(32, 450_000)  # Was 10_000_000

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Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>
Co-authored-by: Christian Clauss <[email protected]>