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)

def open_files(self, what="o", status=None, op="==", nids=None, editor=None):
        """
        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)
        """
        # 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)