code: func getNICsCmd(params *Parameters) *subcommands.Command {
  	return &subcommands.Command{
  		UsageLine: "get-nics [-name <name>]... [-machine <machine>]...",
  		ShortDesc: "retrieves NICs",
  		LongDesc:  "Retrieves network interfaces matching the given names and machines, or all network interfaces if names and machines are omitted.\n\nExample to get all NICs:\ncrimson get-nics\nExample to get the NIC with a certain MAC address:\ncrimson get-nics -mac 00:00:00:00:00:bc",
  		CommandRun: func() subcommands.CommandRun {
  			cmd := &GetNICsCmd{}
  			cmd.Initialize(params)
  			cmd.Flags.Var(flag.StringSlice(&cmd.req.Names), "name", "Name of a NIC to filter by. Can be specified multiple times.")
  			cmd.Flags.Var(flag.StringSlice(&cmd.req.Machines), "machine", "Name of a machine to filter by. Can be specified multiple times.")
  			cmd.Flags.Var(flag.StringSlice(&cmd.req.MacAddresses), "mac", "MAC address to filter by. Can be specified multiple times.")
  			cmd.Flags.Var(flag.StringSlice(&cmd.req.Switches), "switch", "Name of a switch to filter by. Can be specified multiple times.")
  			return cmd
  		},
  	}
  }
docs: // getNICCmd returns a command to get network interfaces.