W1203 logging-fstring-interpolation


'Use %s formatting in logging functions'


Used when a logging statement has a call form of “logging.<logging method>(f”…”)”.Use another type of string formatting instead. You can use % formatting but leave interpolation to the logging function by passing the parameters as arguments. If logging-format-interpolation is disabled then you can use str.format. If logging-not-lazy is disabled then you can use % formatting as normal.


import logging
a = 1
b = 2
logging.debug(f"State: {a}, {b}")
4:0: W1203: Use lazy % formatting in logging functions

Here is how you should use it:

import logging
a = 1
b = 2
logging.debug("State: %d, %d", a, b)
No issues found.

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