unused-format-string-argument / W1304

Message emitted:

Unused format argument %r

Description:

Used when a PEP 3101 format string that uses named fields is used with an argument that is not required by the format string.

Problematic code:

print("{x} {y}".format(x=1, y=2, z=3))  # [unused-format-string-argument]

Correct code:

add_format_target.py:

print("{x} {y} {z}".format(x=1, y=2, z=3))

remove_unused_args.py:

print("{x} {y}".format(x=1, y=2))

Created by the string checker.