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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 read_all(self):
 """Fetches all messages in the database. :rtype: Generator[can.Message] """

        result = self._cursor.execute("SELECT * FROM {}".format(self.table_name)).fetchall()
        return (SqliteReader._assemble_message(frame) for frame in result)