pub trait FunctionOutputField: Send + Sync {
// Required method
fn get_field(
&self,
input_schema: &Schema<DataType>,
cntxt: Context,
fields: &[Field],
) -> Result<Field, PolarsError>;
// Provided method
fn try_serialize(&self, _buf: &mut Vec<u8>) -> Result<(), PolarsError> { ... }
}