What is the difference in total sales between TS Asia and TS Europe in 2019?
{"TS": {"Americas": 67728, "Europe": 3285, "Asia": 646, "Total": 71159, "% of total": 90}, "HPP": {"Americas": 5294, "Europe": 771, "Asia": 1837, "Total": 7902, "% of total": 10}, "Total": {"Americas": 72522, "Europe": 4056, "Asia": 2483, "Total": 79061, "% of total": 100}, "2018 -- TS": {"Americas": 52034, "Europe": 9059, "Asia": 1344, "Total": 62437, "% of total": 86}, "2018 -- HPP": {"Americas": 8424, "Europe": 1266, "Asia": 789, "Total": 10479, "% of total": 14}, "2018 -- Total": {"Americas": 60458, "Europe": 10325, "Asia": 2133, "Total": 72916, "% of total": 100}, "2018 -- % of total": {"Americas": 83, "Europe": 14, "Asia": 3, "Total": 100, "% of total": ""}}
ts_europe = df["TS"]["Europe"]
ts_asia = df["TS"]["Asia"]
answer = ts_europe - ts_asia