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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 get_lists(self):
 """ Returns a collection of lists within this site :rtype: list[SharepointList] """

        url = self.build_url(self._endpoints.get('get_lists'))

        response = self.con.get(url)
        if not response:
            return []

        data = response.json()

        return [self.list_constructor(parent=self, **{self._cloud_data_key: lst}) for lst in data.get('value', [])]