def add_subset_args(parser):
    """Add arguments for specifying a subset of wires to connect."""
    subset_group = parser.add_argument_group('wire subset selection',
        description=
        """
			These arguments allow the specificiation of subsets of wires
			to install, for example, selecting only particular wires
			within a particular cabinet or frame. If no subsets are
			specified, all wires will be included, otherwise the union
			of all specified subsets are included. Use '1.2.*' to select all wires
			between boards in cabinet 1, frame 2. Use '1.*.*' to select all wires
			between boards in cabinet 1. Use '1-2.*.*' to select all
			wires which cross between cabinets 1 and 2.
		"""
        )
    subset_group.add_argument('--subset', nargs='+', type=str, metavar=
        'SUBSET', help='specify the subset of wires to include')
