What is the difference in Total purchase price between Blue Coat and LifeLock?
{"Goodwill": {"Blue Coat": 4084, "LifeLock": 1397, "Total": 5481}, "Intangible assets": {"Blue Coat": 1608, "LifeLock": 1247, "Total": 2855}, "Net liabilities assumed": {"Blue Coat": -1019, "LifeLock": -361, "Total": -1380}, "Total purchase price": {"Blue Coat": 4673, "LifeLock": 2283, "Total": 6956}}
total_purchase_price_blue_coat = df["Total purchase price"]["Blue Coat"]
total_purchase_price_lifelock = df["Total purchase price"]["LifeLock"]
answer = total_purchase_price_blue_coat - total_purchase_price_lifelock