input: Write a function to generate a list of all prime numbers between 1 and a given number n. If n is less than 2, return an empty list.
  assert generate_prime_numbers(10)==[2, 3, 5, 7]
  assert generate_prime_numbers(2)==[2]
  assert generate_prime_numbers(1)==[]
  assert generate_prime_numbers(30)==[2, 3, 5, 7, 11, 13, 17, 19, 23, 29]
  assert generate_prime_numbers(100)==[2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83, 89, 97]
output: if n < 2:
      return []
  primes = []
  for num in range(2, n + 1):
      for i in range(2, int(num**0.5) + 1):
          if num % i == 0:
              break
      else:
          primes.append(num)
  return primes