assert_se(sd_dhcp_client_set_request_option(client, 33) == -EEXIST);
assert_se(sd_dhcp_client_set_request_option(client, 44) == 0);
assert_se(sd_dhcp_client_set_request_option(client, 33) == -EEXIST);
assert_se(sd_dhcp_client_set_request_option(client, 33) == -EEXIST);
assert_se(sd_dhcp_client_set_request_option(client, 44) == 0);
assert_se(sd_dhcp_client_set_request_option(client, 33) == -EEXIST);