text: import os
  
  from anasymod.viewer.viewer import Viewer
  from anasymod.util import call
  
  class SimVisionViewer(Viewer):
      def view(self):
          # build command
          if os.path.isfile(self.target.cfg.vcd_path):
              cmd = [self.cfg.simvision_config.simvision, '-wave', self.target.cfg.vcd_path]
              cmd[1:1] = self.cfg.simvision_config.lsf_opts.split()
              # add waveform file if it exists
              if self.cfg.simvision_config.svcf_config is not None:
                  if os.path.isfile(self.cfg.simvision_config.svcf_config):
                      cmd.extend(['-input', self.cfg.simvision_config.svcf_config])
  
              # run command
              call(cmd)
          else:
              raise Exception(f'ERROR: Result file: {self.target.cfg.vcd_path} does not exist; cannot open waveforms!')