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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 stream(self, recurring=values.unset, trigger_by=values.unset, usage_category=values.unset, limit=None, page_size=None):
 """ Streams TriggerInstance records from the API as a generator stream. This operation lazily loads records as efficiently as possible until the limit is reached. The results are returned as a generator, so this operation is memory efficient. :param TriggerInstance.Recurring recurring: The frequency of recurring UsageTriggers to read :param TriggerInstance.TriggerField trigger_by: The trigger field of the UsageTriggers to read :param TriggerInstance.UsageCategory usage_category: The usage category of the UsageTriggers to read :param int limit: Upper limit for the number of records to return. stream() guarantees to never return more than limit. Default is no limit :param int page_size: Number of records to fetch per request, when not set will use the default value of 50 records. If no page_size is defined but a limit is defined, stream() will attempt to read the limit with the most efficient page size, i.e. min(limit, 1000) :returns: Generator that will yield up to limit results :rtype: list[twilio.rest.api.v2010.account.usage.trigger.TriggerInstance] """

        limits = self._version.read_limits(limit, page_size)

        page = self.page(
            recurring=recurring,
            trigger_by=trigger_by,
            usage_category=usage_category,
            page_size=limits['page_size'],
        )

        return self._version.stream(page, limits['limit'], limits['page_limit'])