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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 lower_case(f):
 """Decorator specifically for turning mssql AST into lowercase"""

    # if it has already been wrapped, we return original
    if hasattr(f, "lower_cased"):
        return f

    @wraps(f)
    def wrapper(*args, **kwargs):
        f.lower_cased = True
        return f(*args, **kwargs).lower()

    return wrapper