input: Write a function to get the sum of even factors of a given number.
  assert get_sum_even_factors(50) == 196
  assert get_sum_even_factors(30) == 42
  assert get_sum_even_factors(12) == 18
output: def get_sum_even_factors(n):
      sum_even_factors = 0
      for i in range(1, n + 1):
          if n % i == 0 and i % 2 == 0:
              sum_even_factors += i
      return sum_even_factors