input: Write a python function to check if any two numbers in a list add up to a given number.
  assert is_sum_possible([1, 2, 3, 9], 8) == False
  assert is_sum_possible([1, 2, 4, 4], 8) == True
  assert is_sum_possible([5, 7, 1, 2], 10) == True
output: def is_sum_possible(numbers, target):
      seen = set()
      for num in numbers:
          if target - num in seen:
              return True
          seen.add(num)
      return False