code: def _run_nonblocking(self, args, input=None):
          
          # Close any existing dialog.
          if self._process:
              self.close()
  
          # Start the new one.
          self._process = subprocess.Popen(args, stdout=subprocess.PIPE)
docs: Internal API: run a non-blocking command with subprocess.
  
          This closes any open non-blocking dialog before running the command.
  
          Parameters
          ----------
          args: Popen constructor arguments
              Command to run.
          input: string
              Value to feed to the stdin of the process.