old_contents: from tambo import Parse
  
  class Transport(Parse):
      """
      This class inherits from the ``Parse`` object that provides the engine
      to parse arguments from the command line, and it extends the functionality
      to be able to dispatch on mapped objects to subcommands.
  
      :param arguments: Should be the *exact* list of arguments coming from ``sys.argv``
      :keyword mapper: A dictionary of mapped subcommands to classes
      """
  
  
      def dispatch(self, mapper=None):
          mapper = mapper or {}
          mapper_keys = mapper.keys()
          for arg in self.arguments:
              if arg in mapper_keys:
                  instance = mapper.get(arg)(self.arguments)
                  return instance.parse_args()
  
new_contents: from tambo import Parse
  
  class Transport(Parse):
      """
      This class inherits from the ``Parse`` object that provides the engine
      to parse arguments from the command line, and it extends the functionality
      to be able to dispatch on mapped objects to subcommands.
  
      :param arguments: Should be the *exact* list of arguments coming from ``sys.argv``
      :keyword mapper: A dictionary of mapped subcommands to classes
      """
  
  
      def dispatch(self):
          mapper_keys = self.mapper.keys()
          for arg in self.arguments:
              if arg in mapper_keys:
                  instance = self.mapper.get(arg)(self.arguments)
                  return instance.parse_args()
  
  
      def subhelp(self):
          """
          This method will look at every value of every key in the mapper
          and will output any ``class.help`` possible to return it as a
          string that will be sent to stdout.
          """
          help_text = self._get_all_help_text()
  
          if help_text:
              return "Available subcommands:\n\n %s\n" % ''.join(help_text)
          return ''
  
      def _get_all_help_text(self):
          help_text_lines = []
          for key, value in self.mapper.items():
              try:
                  help_text = value.help
              except AttributeError:
                  continue
              help_text_lines.append("    %s \t\t %s" % (key, help_text))
          return help_text_lines
  
subject: add subcommand helper printing