code: def __ip_addr(addr, address_family=socket.AF_INET):
      '''
      Returns True if the IP address (and optional subnet) are valid, otherwise
      returns False.
      '''
      mask_max = '32'
      if address_family == socket.AF_INET6:
          mask_max = '128'
  
      try:
          if '/' not in addr:
              addr = '{addr}/{mask_max}'.format(addr=addr, mask_max=mask_max)
      except TypeError:
          return False
  
      ip, mask = addr.rsplit('/', 1)
  
      # Verify that IP address is valid
      try:
          socket.inet_pton(address_family, ip)
      except socket.error:
          return False
  
      # Verify that mask is valid
      try:
          mask = int(mask)
      except ValueError:
          return False
      else:
          if not 1 <= mask <= int(mask_max):
              return False
  
      return Truf __ip_addr(addr, address_family=socket.AF_INET):
      '''
      Returns True if the IP address (and optional subnet) are valid, otherwise
      returns False.
      '''
      mask_max = '32'
      if address_family == socket.AF_INET6:
          mask_max = '128'
  
      try:
          if '/' not in addr:
              addr = '{addr}/{mask_max}'.format(addr=addr, mask_max=mask_max)
      except TypeError:
          return False
  
      ip, mask = addr.rsplit('/', 1)
  
      # Verify that IP address is valid
      try:
          socket.inet_pton(address_family, ip)
      except socket.error:
          return False
  
      # Verify that mask is valid
      try:
          mask = int(mask)
      except ValueError:
          return False
      else:
          if not 1 <= mask <= int(mask_max):
              return False
  
      return True
docs: Returns True if the IP address (and optional subnet) are valid, otherwise
      returns False.