Python中的Class.main编程风格

Question

有人能告诉我这行代码在执行什么吗？

if __name__ == "__main__":
    TwitterHarvester.main(TwitterHarvester, QUEUE, [SEARCH_ROUTING_KEY, TIMELINE_ROUTING_KEY])

这是一个python文件，包含一个名为TwitterHarvester的类，它没有定义主函数。有人能告诉我这条电话在打什么吗？

这是功能的起点；

class TwitterHarvester(BaseHarvester):
    def __init__(self, working_path, stream_restart_interval_secs=30 * 60, mq_config=None, debug=False,
                 connection_errors=5, http_errors=5, debug_warcprox=False, tries=3):
        BaseHarvester.__init__(self, working_path, mq_config=mq_config,
                               stream_restart_interval_secs=stream_restart_interval_secs,
                               debug=debug, debug_warcprox=debug_warcprox, tries=tries)
        self.twarc = None
        self.connection_errors = connection_errors
        self.http_errors = http_errors

    def harvest_seeds(self):
        # Create a twarc
        self._create_twarc()

        # Dispatch message based on type.
        harvest_type = self.message.get("type")
        log.debug("Harvest type is %s", harvest_type)
        if harvest_type == "twitter_search":
            self.search()
        elif harvest_type == "twitter_filter":
            self.filter()
        elif harvest_type == "twitter_sample":
            self.sample()
        elif harvest_type == "twitter_user_timeline":
            self.user_timeline()
        else:
            raise KeyError

    def _create_twarc(self):

Answer 1

TwitterHarvester扩展了BaseHarvester。因此，如果TwitterHarvester没有主函数，那么它应该在BaseHarvester中。

谷歌告诉我，基地收割机是sfm-utils包的一部分。导入行是这里

from sfmutils.harvester import BaseHarvester, Msg

因此，我在sfm-utls源代码中找到了：

class BaseHarvester(BaseConsumer):
    """
    Base class for a harvester, allowing harvesting from a queue or from a file.
    ...
    """
    ...
    @staticmethod
    def main(cls, queue, routing_keys):
        """
        A configurable main() for a harvester.

给你:)