code: def is_dot(ip):
      
      octets = str(ip).split('.')
      if len(octets) != 4:
          return False
      for i in octets:
          try:
              val = int(i)
          except ValueError:
              return False
          if val > 255 or val < 0:
              return False
      return True
docs: Return true if the IP address is in dotted decimal notation.