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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 create_series(self, key=None, tags=[], attrs={}):
 """Create a new series with an optional string key. A list of tags and a map of attributes can also be optionally supplied. :param string key: (optional) a string key for the series :param list tags: (optional) the tags to create the series with :param dict attrs: (optional) the attributes to the create the series with :rtype: :class:`tempodb.response.Response` object"""


        body = protocol.make_series_key(key, tags, attrs)
        resp = self.session.post(endpoint.SERIES_ENDPOINT, body)
        return resp