What is the total incremental costs of obtaining a contract and contract fulfillment costs in 2018 and 2019?
{"Opening balance, January 1": {"2019": 707, "2018": 636}, "Incremental costs of obtaining a contract and contract fulfillment costs": {"2019": 602, "2018": 567}, "Amortization included in operating costs": {"2019": -523, "2018": -477}, "Impairment charges included in operating costs": {"2019": -3, "2018": -19}, "Ending balance, December 31": {"2019": 783, "2018": 707}}
incremental_costs_2019 = df["Incremental costs of obtaining a contract and contract fulfillment costs"]["2019"]
incremental_costs_2018 = df["Incremental costs of obtaining a contract and contract fulfillment costs"]["2018"]
answer = incremental_costs_2019 + incremental_costs_2018