code: def hexify(number):
      
      if( isinstance(number, int) == False ):
          raise TypeError('hexify(): expected integer, not {}'.format(type(number)))
  
      if number < 0:
          raise ValueError('Invalid number to hexify - must be positive')
  
      result = hex(int(number)).replace('0x', '').upper()
      if divmod(len(result), 2)[1] == 1:
          # Padding
          result = '0{}'.format(result)
      return result
docs: Convert integer to hex string representation, e.g. 12 to '0C'