pub fn check_is_valid_struct_cast(
input_dtype: &DataType,
output_dtype: &DataType,
output_name: &PlSmallStr,
) -> PolarsResult<()>pub fn check_is_valid_struct_cast(
input_dtype: &DataType,
output_dtype: &DataType,
output_name: &PlSmallStr,
) -> PolarsResult<()>