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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(root_dir):
 """ Remove all files and directories in supplied root directory. """

    for dirpath, dirnames, filenames in os.walk(os.path.abspath(root_dir)):
        for filename in filenames:
            os.remove(os.path.join(root_dir, filename))

        for dirname in dirnames:
            shutil.rmtree(os.path.join(root_dir, dirname))