What is the difference in Net revenues from external customers between Activision and Blizzard?
{"Segment Revenues -- Net revenues from external customers": {"Activision": 2458, "Blizzard": 2238, "King": 2086, "Total": 6782}, "Segment Revenues -- Intersegment net revenues (1)": {"Activision": "\u2014", "Blizzard": 53, "King": "\u2014", "Total": 53}, "Segment Revenues -- Segment net revenues": {"Activision": 2458, "Blizzard": 2291, "King": 2086, "Total": 6835}, "Segment Revenues -- Segment operating income": {"Activision": 1011, "Blizzard": 685, "King": 750, "Total": 2446}}
activision_revenue = df["Segment Revenues -- Net revenues from external customers"]["Activision"]
blizzard_revenue = df["Segment Revenues -- Net revenues from external customers"]["Blizzard"]
answer = activision_revenue - blizzard_revenue