def unwrap_nullable(data_type):
if is_nullable_type(data_type):<EOL><INDENT>return data_type.data_type, True<EOL><DEDENT>else:<EOL><INDENT>return data_type, False<EOL><DEDENT>
Convenience method to unwrap Nullable from around a DataType.

Args:
    data_type (DataType): The target to unwrap.

Return:
    Tuple[DataType, bool]: The underlying data type and a bool indicating
        whether the input type was nullable.