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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def clean_locale(configuration, locale):
 """ Strips out the warning from all of a locale's translated po files about being an English source file. Iterates over machine-generated files. """

    dirname = configuration.get_messages_dir(locale)
    if not dirname.exists():
        # Happens when we have a supported locale that doesn't exist in Transifex
        return
    for filename in dirname.files('*.po'):
        clean_file(configuration, dirname.joinpath(filename))