input: def is_prime(num: int) -> bool:
      """ Determines if the given number is a prime number.
      >>> is_prime(17)
      True
      >>> is_prime(20)
      False
      """
      if num <= 1:
          return False
      for i in range(2, int(num**0.5) + 1):
          if num % i == 0:
              return False
      return True
output:     if num <= 1:
          return False
      for i in range(2, int(num**0.5) + 1):
          if num % i == 0:
              return False
      return True