code: def create_primes(threshold):
      
      if threshold == 2:
          return [2]
  
      elif threshold < 2:
          return []
  
      numbers = list(range(3, threshold+1, 2))
      root_of_threshold = threshold ** 0.5
      half = int((threshold+1)/2-1)
      idx = 0
      counter = 3
      while counter <= root_of_threshold:
          if numbers[idx]:
              idy = int((counter*counter-3)/2)
              numbers[idy] = 0
              while idy < half:
                  numbers[idy] = 0
                  idy += counter
          idx += 1
          counter = 2*idx+3
      return [2] + [number for number in numbers if number]
docs: Generate prime values using sieve of Eratosthenes method.
  
      Args:
          threshold (int):
              The upper bound for the size of the prime values.
  
      Returns (List[int]):
          All primes from 2 and up to ``threshold``.