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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 from_statement(cls, statement):
 """ Create a selection function from a statement """

        if statement[0] in ["TS", "TIMESTAMP", "UTCTIMESTAMP", "UTCTS"]:
            return TimestampFunction.from_statement(statement)
        elif statement[0] in ["NOW", "UTCNOW"]:
            return NowFunction.from_statement(statement)
        else:
            raise SyntaxError("Unknown function %r" % statement[0])