What is the total summed ownership requirement for the Executive officers?
{"Samir Kapuria": {"Ownership Requirement (1) (# of shares)": 39665, "Holdings as of October 25, 2019(# of shares)": 186735}, "Vincent Pilette": {"Ownership Requirement (1) (# of shares)": 85941, "Holdings as of October 25, 2019(# of shares)": 785906}, "Scott C. Taylor": {"Ownership Requirement (1) (# of shares)": 52887, "Holdings as of October 25, 2019(# of shares)": 408724}}
total_ownership_req = df["Samir Kapuria"]["Ownership Requirement (1) (# of shares)"] + df["Vincent Pilette"]["Ownership Requirement (1) (# of shares)"] + df["Scott C. Taylor"]["Ownership Requirement (1) (# of shares)"]
answer = total_ownership_req