def refresh_persistent_maps(self):
for robot in self._robots:<EOL><INDENT>resp2 = (requests.get(urljoin(<EOL>self.ENDPOINT,<EOL>'<STR_LIT>'.format(robot.serial)),<EOL>headers=self._headers))<EOL>resp2.raise_for_status()<EOL>self._persistent_maps.update({robot.serial: resp2.json()})<EOL><DEDENT>
Get information about persistent maps of the robots.

:return: