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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 insert(self, dct, toa=None, comment=""):
 """Create a document :param dict dct: :param toa toa: Optional time of action, triggers this to be handled as a future insert action for a new document :param str comment: A comment :rtype str: :returns string bson id: """

        if self.schema:
            jsonschema.validate(dct, self.schema)

        bson_obj = yield self.collection.insert(dct)

        raise Return(bson_obj.__str__())