Added support to report low battery for garage doors (#163)

Author: fabianluque

pymyq/garagedoor.py

@@ -51,6 +51,11 @@ def open_allowed(self) -> bool:
         """Return whether the device can be opened unattended."""
         return self.device_json["state"].get("is_unattended_open_allowed") is True
 
+    @property
+    def low_battery(self) -> bool:
+        """Return whether the device has low battery."""
+        return self.device_json["state"].get("dps_low_battery_mode") is True
+
     @property
     def device_state(self) -> Optional[str]:
         """Return the current state of the device."""