code: def _run_cnvkit_single(data, background=None):
      
      if not background:
          background = []
      ckouts = _run_cnvkit_shared([data], background)
      if not ckouts:
          return [data]
      else:
          assert len(ckouts) == 1
          return _associate_cnvkit_out(ckouts, [data])
docs: Process a single input file with BAM or uniform background.