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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 multi_post(self, urls, query_params=None, data=None, to_json=True, send_as_file=False):
 """Issue multiple POST requests. Args: urls - A string URL or list of string URLs query_params - None, a dict, or a list of dicts representing the query params data - None, a dict or string, or a list of dicts and strings representing the data body. to_json - A boolean, should the responses be returned as JSON blobs send_as_file - A boolean, should the data be sent as a file. Returns: a list of dicts if to_json is set of requests.response otherwise. Raises: InvalidRequestError - Can not decide how many requests to issue. """

        return self._multi_request(
            MultiRequest._VERB_POST, urls, query_params,
            data, to_json=to_json, send_as_file=send_as_file,
        )