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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 if_match(self):
 """ Get the If-Match option of a request. :return: the If-Match values or [] if not specified by the request :rtype : list """

        value = []
        for option in self.options:
            if option.number == defines.OptionRegistry.IF_MATCH.number:
                value.append(option.value)
        return value