What is the difference in the perpetuity growth rate between Bell Wireless and Bell Wireline?
{"Bell Wireless": {"PERPETUITY GROWTH RATE": 0.8, "DISCOUNT RATE": 9.1}, "Bell Wireline": {"PERPETUITY GROWTH RATE": 1.0, "DISCOUNT RATE": 6.0}, "Bell Media": {"PERPETUITY GROWTH RATE": 1.0, "DISCOUNT RATE": 8.0}}
bell_wireline_perpetuity_growth_rate = df["Bell Wireline"]["PERPETUITY GROWTH RATE"]
bell_wireless_perpetuity_growth_rate = df["Bell Wireless"]["PERPETUITY GROWTH RATE"]
answer = bell_wireline_perpetuity_growth_rate - bell_wireless_perpetuity_growth_rate