# Return sum of even Fibonacci numbers that # do not exceed 4000000 def sum_fib_even(): sum = 2 fib1 = 1 fib2 = 2 fib3 = 3 while fib3 < 4000000: if (fib3 % 2) == 0: sum += fib3 fib1 = fib2 fib2 = fib3 fib3 = fib1 + fib2 return sum sum_fib_even()