Make Python's `warnings.warn()` not mention itself

Question

My minimum example is

#!/usr/bin/python3

import warnings

warnings.warn(\'Run Forest run!\', stacklevel=2)
warnings.warn(\'Run Forest run!\')

Answer 1

Turns out it is possible to let warnings.warn() collect all the info and just costumize the way the info is printed:

#!/usr/bin/python3

import warnings

def warning_on_one_line(message, category, filename, lineno, file=None, line=None):
    return '%s:%s: %s: %s\n' % (filename, lineno, category.__name__, message)

warnings.formatwarning = warning_on_one_line

warnings.warn('Run Forest run!', stacklevel=2)
warnings.warn('Run Forest run!')

Output:

sys:1: UserWarning: Run Forest run!
./file.py:15: UserWarning: Run Forest run!

Source: Python module of the week