docs: def create_process(self, command, shell=True, stdout=None, stderr=None,
                         env=None):
          """
          Execute a process using subprocess.Popen, setting the backend's DISPLAY
          """
          env = env if env is not None else dict(os.environ)
          env['DISPLAY'] = self.display
          return subprocess.Popen(command, shell=shell,
                                  stdout=stdout, stderr=stderr,
                                  env=env)