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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 db_type(self, connection):
 """ The type of the field to insert into the database. """

        conn_module = type(connection).__module__
        if "mysql" in conn_module:
            return "bigint AUTO_INCREMENT"
        elif "postgres" in conn_module:
            return "bigserial"
        return super(BigAutoField, self).db_type(connection)