code: def open_files(self, what="o", status=None, op="==", nids=None, editor=None):
          
          # Build list of files to analyze.
          files = []
          for task in self.iflat_tasks(status=status, op=op, nids=nids):
              lst = task.select_files(what)
              if lst:
                  files.extend(lst)
  
          return Editor(editor=editor).edit_files(files)
docs: Open the files of the flow inside an editor (command line interface).
  
          Args:
              what: string with the list of characters selecting the file type
                    Possible choices:
                      i ==> input_file,
                      o ==> output_file,
                      f ==> files_file,
                      j ==> job_file,
                      l ==> log_file,
                      e ==> stderr_file,
                      q ==> qout_file,
                      all ==> all files.
              status: if not None, only the tasks with this status are select
              op: status operator. Requires status. A task is selected
                  if task.status op status evaluates to true.
              nids: optional list of node identifiers used to filter the tasks.
              editor: Select the editor. None to use the default editor ($EDITOR shell env var)