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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, activity_name=values.unset, activity_sid=values.unset, available=values.unset, friendly_name=values.unset, target_workers_expression=values.unset, task_queue_name=values.unset, task_queue_sid=values.unset, limit=None, page_size=None):
 """ Streams WorkerInstance 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 unicode activity_name: Filter by workers that are in a particular Activity by Friendly Name :param unicode activity_sid: Filter by workers that are in a particular Activity by SID :param unicode available: Filter by workers that are available or unavailable. :param unicode friendly_name: Filter by a worker's friendly name :param unicode target_workers_expression: Filter by workers that would match an expression on a TaskQueue. :param unicode task_queue_name: Filter by workers that are eligible for a TaskQueue by Friendly Name :param unicode task_queue_sid: Filter by workers that are eligible for a TaskQueue by SID :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.taskrouter.v1.workspace.worker.WorkerInstance] """

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

        page = self.page(
            activity_name=activity_name,
            activity_sid=activity_sid,
            available=available,
            friendly_name=friendly_name,
            target_workers_expression=target_workers_expression,
            task_queue_name=task_queue_name,
            task_queue_sid=task_queue_sid,
            page_size=limits['page_size'],
        )

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