input: Write a function to generate prime numbers less than a given number using a generator.
  assert list(generate_prime_numbers(10)) == [2, 3, 5, 7]
  assert list(generate_prime_numbers(20)) == [2, 3, 5, 7, 11, 13, 17, 19]
  assert list(generate_prime_numbers(5)) == [2, 3]
output: def generate_prime_numbers(limit):
      def is_prime(num):
          if num < 2:
              return False
          for i in range(2, int(num**0.5) + 1):
              if num % i == 0:
                  return False
          return True
  
      for num in range(2, limit):
          if is_prime(num):
              yield num