fix num_bits always returning full size

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Before we can merge this PR, please make sure that all the following items have been
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• Targeted PR against correct branch (main)
• Linked to Github issue with discussion and accepted design OR have an explanation in the PR that describes this work.
• Wrote unit tests
• Updated relevant documentation in the code
• Added a relevant changelog entry to the Pending section in CHANGELOG.md
• Re-reviewed Files changed in the Github PR explorer

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Apparently lint job is broken if there're changes done to md files

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@Pratyush CI is green