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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 observe(self):
 """ Check if the request is an observing request. :return: 0, if the request is an observing request """

        for option in self.options:
            if option.number == defines.OptionRegistry.OBSERVE.number:
                # if option.value is None:
                #    return 0
                if option.value is None:
                    return 0
                return option.value
        return None