        Output the "previous" branch(es) in the patch series containing the
        current or named branch.  The "previous" branch(es) being one step
        away by default.

        Options:
          -i            show dependencies based on index instead of branch
          -w            show dependencies based on working tree instead of branch
          -n <steps>    take ``<steps>`` "previous" steps (default 1)
          --all         take as many "previous" steps as possible (aka ``-a``)
          --verbose     show containing series name(s) (aka ``-v``)

        The ``-n`` option may also be given as ``--count`` or ``--count=<n>``.

        To list all dependencies of a branch see the ``--deps`` option of
        the `tg info`_ command.

        See also NAVIGATION_ for full details on "previous" steps.

