Refactor multivariate_calculus.py:chain_rule(f,xf,yf,zf,respect,s)

[AoWangPhilly]

I've selected multivariate_calculus.py:chain_rule(f,xf,yf,zf,respect,s) for refactoring, which is a unit of 16 lines of code and 6 parameters. Addressing this will make our codebase more maintainable and improve Better Code Hub's Keep Unit Interfaces Small guideline rating! 👍

Here's the gist of this guideline:

• Definition 📖
  Limit the number of parameters per unit to at most 4.
• Why❓
  Keeping the number of parameters low makes units easier to understand, test and reuse.
• How 🔧
  Reduce the number of parameters by grouping related parameters into objects. Alternatively, try extracting parts of units that require fewer parameters.

You can find more info about this guideline in Building Maintainable Software. 📖

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ℹ️ To know how many other refactoring candidates need addressing to get a guideline compliant, select some by clicking on the 🔲 next to them. The risk profile below the candidates signals (✅) when it's enough! 🏁

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Good luck and happy coding! ✨ 💯