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percent-format-positional-count-mismatch (F507)#

Derived from the Pyflakes linter.

What it does#

Checks for printf-style format strings that have a mismatch between the number of positional placeholders and the number of substitution values.

Why is this bad?#

When a printf-style format string is provided with too many or too few substitution values, it will raise a TypeError at runtime.


"%s, %s" % ("Hello", "world", "!")

Use instead:

"%s, %s" % ("Hello", "world")