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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 find_one_by_id(self, _id):
 """ Find a single document by id :param str _id: BSON string repreentation of the Id :return: a signle object :rtype: dict """

        document = (yield self.collection.find_one({"_id": ObjectId(_id)}))
        raise Return(self._obj_cursor_to_dictionary(document))