input: Write a function to determine if a number provided by the user is prime or not. Return "prime" if the number is prime and "not prime" if the number is not prime. If the provided number is less than 2, return "not prime".
  
  def is_prime(num):
      if num < 2:
          return "not prime"
      for i in range(2, num):
          if num % i == 0:
              return "not prime"
      return "prime"
  
  assert is_prime(17) == "prime"
  assert is_prime(4) == "not prime"
  assert is_prime(2) == "prime"
  assert is_prime(1) == "not prime"
  assert is_prime(0) == "not prime"
output: def is_prime(num):
      if num < 2:
          return "not prime"
      for i in range(2, num):
          if num % i == 0:
              return "not prime"
      return "prime"