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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 chown_r(path: str, user: str, group: str) -> None: """ Performs a recursive ``chown``. Args: path: path to walk down user: user name or ID group: group name or ID As per http://stackoverflow.com/questions/2853723 """

    for root, dirs, files in os.walk(path):
        for x in dirs:
            shutil.chown(os.path.join(root, x), user, group)
        for x in files:
            shutil.chown(os.path.join(root, x), user, group)