input: from typing import Any
  
  def is_prime_number(num: Any) -> str:
      """ Determine if the given number is a prime number or not.
      >>> is_prime_number(17)
      '17 is a prime number.'
      >>> is_prime_number(4)
      '4 is not a prime number.'
      """
      # Convert input to integer
      num = int(num)
      
      # Set initial value
      is_prime = True
      
      # Check for prime
      for i in range(2, num):
          if num % i == 0:
              is_prime = False
              break
      
      # Return result
      if is_prime:
          return f'{num} is a prime number.'
      else:
          return f'{num} is not a prime number.'
output:     if num <= 1:
          return f'{num} is not a prime number.'