fix: non-int issue and remove useless variables

[Helias]

Reference Issue

closes #14

What does this implement/fix? Explain your changes.

• Cast to int frame_length and frame_step as suggested from the issue.
• Remove unused variables

Any other comments?

Thanks aacarneiro@95a8c78 @aacarneiro

[SuperKogito]

Thank you for your contribution.
well technically the suggested changes in #14 were already implemented so functionality-wise I don't see, how is this a fix tbh.
All you did here is move the int() outside of the function call, which might be a better practice.
I will need to further test this though.

[Helias]

With this fix the error TypeError: can't multiply sequence by non-int of type 'float' does not appear anymore

I have to use this fix for my personal experiments, for this reason I investigate it and made the PR

[SuperKogito]

Thank you for contributing 👏
Just tested this and it works 👍 .