def _create_types_map(sqltypes):
    """Take a types module and utilising the `dir` function create a
    mapping from the string value of that attribute to the SQLAlchemy
    type instance.
    """
    sql_types_map = {
        item.lower(): getattr(sqltypes, item)
        for item in dir(sqltypes)
        if item[0].isupper()
    }

    return sql_types_map