code: def pip_list(self, name=None, prefix=None, abspath=True):
          
          if (name and prefix) or not (name or prefix):
              raise TypeError("conda pip: exactly one of 'name' ""or 'prefix' "
                              "required.")
  
          if name:
              prefix = self.get_prefix_envname(name)
  
          pip_command = os.sep.join([prefix, 'bin', 'python'])
          cmd_list = [pip_command, PIP_LIST_SCRIPT]
          process_worker = ProcessWorker(cmd_list, pip=True, parse=True,
                                         callback=self._pip_list,
                                         extra_kwargs={'prefix': prefix})
          process_worker.sig_finished.connect(self._start)
          self._queue.append(process_worker)
          self._start()
  
          return process_worker
docs: Get list of pip installed packages.