def check_for_null_type_columns_from_forward_refs(config: "OrmarConfig") -> bool:
    """
    Check is any column is of NUllType() meaning it's empty column from ForwardRef

    :param config: OrmarConfig of the Model without sqlalchemy table constructed
    :type config: Model class OrmarConfig
    :return: result of the check
    :rtype: bool
    """
    return not any(
        isinstance(col.type, sqlalchemy.sql.sqltypes.NullType) for col in config.columns
    )

    Check is any column is of NUllType() meaning it's empty column from ForwardRef

    :param config: OrmarConfig of the Model without sqlalchemy table constructed
    :type config: Model class OrmarConfig
    :return: result of the check
    :rtype: bool
    
ormar/models/helpers/sqlalchemy.py