Fix Syntax Error with Nested Single Quotes in f-string

[sourcery-ai]

There is a potential syntax error when using single quotes inside an f-string that is also enclosed in single quotes. This can lead to syntax errors in the code.

Problem:
Using single quotes for both the outer f-string and the inner string can cause a conflict, resulting in a syntax error.

Suggested Fix:
To resolve this issue, use double quotes for the outer f-string. For example, change:

ylabel=f'MSE [{units['mse']}]',

To:

ylabel=f"MSE [{units['mse']}]",

This change avoids the conflict with the single quotes inside the f-string and should resolve the syntax error.

Action Items:

• Review the codebase for similar instances of nested single quotes in f-strings.
• Apply the suggested fix where applicable to prevent syntax errors.

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I created this issue for @ruancomelli from #204 (comment).