What is the total pension benefits accrued by the company in 2018 and 2019?
{"Pension benefits": {"2019": 8566, "2018": 10905}, "Other post-employment benefits": {"2019": 23508, "2018": 21330}, "Accrued benefit liabilities": {"2019": 32074, "2018": 32235}}
pension_benefits_2019 = df["Pension benefits"]["2019"]
pension_benefits_2018 = df["Pension benefits"]["2018"]
answer = pension_benefits_2019 + pension_benefits_2018