code: def get_usage(self, program_name=None):
          
          program_name = os.path.relpath(program_name or sys.argv[0] or 'Dummy',
                                         self.base_dir)
          commands = OrderedDict(self.gather_commands())
          options = gather_command_line_options()
          long_usage = format_usage(program_name, self.doc, commands, options)
          # internal usage is a workaround because docopt cannot handle spaces
          # in program names. So for parsing we use 'dummy' as the program name.
          # for printing help etc. we want to use the actual program name.
          internal_usage = format_usage('dummy', self.doc, commands, options)
          short_usage = printable_usage(long_usage)
          return short_usage, long_usage, internal_usage
docs: Get the commandline usage string for this experiment.