What is the difference in net accounts receivable from 2018 to 2019?
{"Trade accounts receivable": {"2019": 526.6, "2018": 469.2}, "Less: Allowance for doubtful accounts": {"2019": -2.2, "2018": -2.3}, "Product returns reserve": {"2019": -0.3, "2018": -0.2}, "Partner programs and other obligations": {"2019": -49.8, "2018": -28.5}, "Accounts receivable, net (1)": {"2019": 474.3, "2018": 438.2}}
accounts_receivable_net_1_2019 = df["Accounts receivable, net (1)"]["2019"]
accounts_receivable_net_1_2018 = df["Accounts receivable, net (1)"]["2018"]
answer = accounts_receivable_net_1_2019 - accounts_receivable_net_1_2018