code: def set_backend_for_mayavi(self, command):
          
          calling_mayavi = False
          lines = command.splitlines()
          for l in lines:
              if not l.startswith('#'):
                  if 'import mayavi' in l or 'from mayavi' in l:
                      calling_mayavi = True
                      break
          if calling_mayavi:
              message = _("Changing backend to Qt for Mayavi")
              self._append_plain_text(message + '\n')
              self.silent_execute("%gui inline\n%gui qt")
docs: Mayavi plots require the Qt backend, so we try to detect if one is
          generated to change backends