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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 _validate_path(path):
 """Sorts path values from largest to smallest. Will warn if path parameter was not already sorted. """

    if path is None:
        return None

    new_path = np.array(sorted(set(path), reverse=True))
    if new_path[0] != path[0]:
        print("Warning: Path must be sorted largest to smallest.")

    return new_path