#### SUMMARY
This feature would implement a UpdateUserName command for the Accounts category of redfish_command, to update user name. And also implement a UpdatePasswordPolicy command for the Accounts category of redfish_command to change password policy.

##### ISSUE TYPE
- Feature Idea

##### COMPONENT NAME
redfish_command

##### ADDITIONAL INFORMATION
These 2 commands would help user to update user name or update password policy

"""
        Get Redfish ExtendedInfo message from response payload if present
        :param error: an HTTPError exception
        :type error: HTTPError
        :return: the ExtendedInfo message if present, else standard HTTP error
        """
        msg = http_client.responses.get(error.code, '')
        if error.code >= 400:
            try:
                body = error.read().decode('utf-8')
                data = json.loads(body)
                ext_info = data['error']['@Message.ExtendedInfo']
                msg = ext_info[0]['Message']
            except Exception:
                pass
        return msg
    def _init_session(self):