def main():
    a = 5

    if iseven(a):
        print(f"{a} is even.")
    else:
        print(f"{a} is odd.")

def iseven(a):
    return True

if __name__ == "__main__":
    main()

We'll start by fixing this. Then, we'll make a function that tests if a number is prime. Then we will try to generate the first million prime numbers. But, quickly!

def iseven_bad(a):

  b = float(a) / 2
  c = str(b)
  d = c[-1]

  if d == '0':
      return True

  return False

def iseven_good(a):

  b = a % 2
  if b == 0:
      return True

  return False

def iseven_bit(a):

  if a & 1:
      return False
  else:
      return True

def iseven_count(a):

  b = a
  while b > 0:
      b = b - 2
      if b == 1:
          return False

  return True

</Code>

def test():
    # set up the array
    a = []
    for x in range(1_000_000):
        a.append(random.randint(1,1000))

    start = time.perf_counter_ns()

    c = 0
    for x in range(1_000_000):
        r = iseven_good(a[c])
        c = c + 1

    ms = (time.perf_counter_ns() - start) / 1_000_000
    print(f"run time: {ms} ms")