code: def demux(sel, di, ls_do):
      
      N = len(ls_do)
      @always_comb
      def _demux():
          for i in range(N):
              ls_do[i].next = 0
              if i == sel:
                  ls_do[i].next = di
      return _demux
docs: Demultiplexes an input signal to a list of output signals
              ls_do[sel] =  di
  
              sel - select index
              di - input signal
              ls_do - list of output signals