What was the change in the Cash and cash equivalents from 2018 to 2019?
{"Cash and cash equivalents": {"2019": 4777, "2018": 1008}, "Restricted cash": {"2019": 72, "2018": 70}, "Restricted cash included in other assets, noncurrent": {"2019": "--   ", "2018": 70}, "Total cash, cash equivalents, and restricted cash in the balance sheet ": {"2019": 4849, "2018": 1148}}
cash_and_cash_equivalents_2019 = df["Cash and cash equivalents"]["2019"]
cash_and_cash_equivalents_2018 = df["Cash and cash equivalents"]["2018"]
answer = cash_and_cash_equivalents_2019 - cash_and_cash_equivalents_2018