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% operator to format string can cause production risk

Count one violation each time a string use the % operator. bad

print("%s is %s" % ("`$`", "fine"))

good

print("{0} is {1}, much {1}".format("format", "better"))

Why you should care

Future python version will promote usage of format().

If possible, prefer using the format() function to perform string-formatting instead of the % operator. The former provides more advanced options, allows you to reuse arguments in your string and removes ambiguity.

Business Impacts

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CAST recommendations

References

https://www.quantifiedcode.com/knowledge-base/maintainability/Prefer%20%60format%28%29%60%20over%20string%20interpolation%20operator/4ACGxFj1

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For reference only. For the complete details please refer the original article
https://doc.casthighlight.com/alt_stringformat-avoid-operator-to-format-string/