input: from typing import List
  
  
  def is_prime(num: int) -> bool:
      """ Determines if the given number is prime or not. A prime number is a
      natural number greater than 1 that has no positive divisors other than 1
      and itself.
      >>> is_prime(17)
      True
      >>> is_prime(12)
      False
      """
      if num <= 1:
          return False
      for i in range(2, num):
          if num % i == 0:
              return False
      return True
output:     if num <= 1:
          return False
      if num == 2:
          return True
      if num % 2 == 0:
          return False
      for i in range(3, int(num**0.5) + 1, 2):
          if num % i == 0:
              return False
      return True