* add circular convolution
* [pre-commit.ci] auto fixes from pre-commit.com hooks
for more information, see https://pre-commit.ci
* add type hint for __init__
* rounding off final values to 2 and minor changes
* add test case for unequal signals
* changes in list comprehension and enumeraton
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Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>