How to use "sort_field"?

Hello 

How could I filter test cases by Author?

starting_row = 1
number_of_rows = 10000000
sort_field = {"AuthorId": 1}
sort_direction = "ASC"
get_test_cases = f"projects/{project_id}/test-cases?starting_row={starting_row}&number_of_rows={number_of_rows}&sort_field={sort_field}&sort_direction={sort_direction}"

I've tried to use sort_field = "Name" is doesn't work as well.

Best Regards,
N