Add support for gosund miot plug (cuco.plug.cp1)

this is just a poc to show how the new api could function

miio/__init__.py

@@ -22,6 +22,7 @@
 from miio.exceptions import DeviceError, DeviceException
 from miio.fan import Fan, FanP5, FanSA1, FanV2, FanZA1, FanZA4
 from miio.gateway import Gateway
+from miio.gosund_plug import GosundPlug
 from miio.heater import Heater
 from miio.philips_bulb import PhilipsBulb, PhilipsWhiteBulb
 from miio.philips_eyecare import PhilipsEyecare

miio/gosund_plug.py

@@ -0,0 +1,35 @@
+import logging
+from dataclasses import dataclass, field
+
+from .click_common import command, format_output
+from .miot_device import MiotDevice
+
+_LOGGER = logging.getLogger(__name__)
+
+
+@dataclass
+class GosundPlugStatus:
+    _max_properties = 1
+    state: bool = field(metadata={"siid": 2, "piid": 1})
+
+
+class GosundPlug(MiotDevice):
+    """Support for gosund miot plug (cuco.plug.cp1)."""
+
+    _MAPPING = GosundPlugStatus
+
+    @command()
+    def status(self) -> GosundPlugStatus:
+        """Return current state of the plug."""
+
+        return self.get_properties_for_dataclass(GosundPlugStatus)
+
+    @command(default_output=format_output("Powering on"))
+    def on(self):
+        """Power on."""
+        return self.set_property(state=True)
+
+    @command(default_output=format_output("Powering off"))
+    def off(self):
+        """Power off."""
+        return self.set_property(state=False)