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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 _remove_files(files):
 """ Remove all given files. Args: files (list):
 List of filenames, which will be removed. """

    logger.debug("Request for file removal (_remove_files()).")

    for fn in files:
        if os.path.exists(fn):
            logger.debug("Removing '%s'." % fn)
            os.remove(fn)