Use stacklevel=2 for warnings to report on callsites (#1219)

Use stacklevel=2 for warnings, as this will correctly show the callsite
instead of the line where the warning is reported.

Currently:
```
kasa/__init__.py:110
  /home/tpr/code/python-kasa/kasa/__init__.py:110: DeprecationWarning: SmartDevice is deprecated, use IotDevice from package kasa.iot instead or use Discover.discover_single() and Device.connect() to support new protocols
    warn(
```

After:
```
kasa/tests/smart/modules/test_contact.py:3
  /home/tpr/code/python-kasa/kasa/tests/smart/modules/test_contact.py:3: DeprecationWarning: SmartDevice is deprecated, use IotDevice from package kasa.iot instead or use Discover.discover_single() and Device.connect() to support new protocols
    from kasa import Module, SmartDevice

``` 

Currently:
```
kasa/tests/test_lightstrip.py: 56 warnings
  /home/tpr/code/python-kasa/kasa/device.py:559: DeprecationWarning: effect is deprecated, use: Module.LightEffect in device.modules instead
    warn(msg, DeprecationWarning, stacklevel=1)
```

After:
```
kasa/tests/test_lightstrip.py::test_effects_lightstrip_set_effect_transition[500-KL430(US)_2.0_1.0.9.json]
  /home/tpr/code/python-kasa/kasa/tests/test_lightstrip.py:62: DeprecationWarning: set_effect is deprecated, use: Module.LightEffect in device.modules instead
    await dev.set_effect("Candy Cane")
```

kasa/__init__.py

@@ -102,7 +102,7 @@ deprecated_classes = {
 
 def __getattr__(name):
     if name in deprecated_names:
-        warn(f"{name} is deprecated", DeprecationWarning, stacklevel=1)
+        warn(f"{name} is deprecated", DeprecationWarning, stacklevel=2)
         return globals()[f"_deprecated_{name}"]
     if name in deprecated_smart_devices:
         new_class = deprecated_smart_devices[name]
@@ -112,13 +112,13 @@ def __getattr__(name):
             + f"from package {package_name} instead or use Discover.discover_single()"
             + " and Device.connect() to support new protocols",
             DeprecationWarning,
-            stacklevel=1,
+            stacklevel=2,
         )
         return new_class
     if name in deprecated_classes:
         new_class = deprecated_classes[name]
         msg = f"{name} is deprecated, use {new_class.__name__} instead"
-        warn(msg, DeprecationWarning, stacklevel=1)
+        warn(msg, DeprecationWarning, stacklevel=2)
         return new_class
     raise AttributeError(f"module {__name__!r} has no attribute {name!r}")
 

kasa/device.py

@@ -545,7 +545,7 @@ class Device(ABC):
             msg = f"{name} is deprecated"
             if module:
                 msg += f", use: {module} in device.modules instead"
-            warn(msg, DeprecationWarning, stacklevel=1)
+            warn(msg, DeprecationWarning, stacklevel=2)
             return self.device_type == dep_device_type_attr[1]
         # Other deprecated attributes
         if (dep_attr := self._deprecated_other_attributes.get(name)) and (
@@ -556,6 +556,6 @@ class Device(ABC):
             dev_or_mod = self.modules[mod] if mod else self
             replacing = f"Module.{mod} in device.modules" if mod else replacing_attr
             msg = f"{name} is deprecated, use: {replacing} instead"
-            warn(msg, DeprecationWarning, stacklevel=1)
+            warn(msg, DeprecationWarning, stacklevel=2)
             return getattr(dev_or_mod, replacing_attr)
         raise AttributeError(f"Device has no attribute {name!r}")

kasa/interfaces/energy.py

@@ -182,6 +182,6 @@ class Energy(Module, ABC):
     def __getattr__(self, name):
         if attr := self._deprecated_attributes.get(name):
             msg = f"{name} is deprecated, use {attr} instead"
-            warn(msg, DeprecationWarning, stacklevel=1)
+            warn(msg, DeprecationWarning, stacklevel=2)
             return getattr(self, attr)
         raise AttributeError(f"Energy module has no attribute {name!r}")

kasa/iot/iotdevice.py

@@ -472,7 +472,7 @@ class IotDevice(Device):
     async def get_time(self) -> datetime:
         """Return current time from the device, if available."""
         msg = "Use `time` property instead, this call will be removed in the future."
-        warn(msg, DeprecationWarning, stacklevel=1)
+        warn(msg, DeprecationWarning, stacklevel=2)
         return self.time
 
     async def get_timezone(self) -> tzinfo:
@@ -480,7 +480,7 @@ class IotDevice(Device):
         msg = (
             "Use `timezone` property instead, this call will be removed in the future."
         )
-        warn(msg, DeprecationWarning, stacklevel=1)
+        warn(msg, DeprecationWarning, stacklevel=2)
         return self.timezone
 
     @property  # type: ignore

kasa/tests/fakeprotocol_smart.py

@@ -202,12 +202,12 @@ class FakeSmartTransport(BaseTransport):
                 else:
                     warn(
                         f"Could not find child SMART fixture for {child_info}",
-                        stacklevel=1,
+                        stacklevel=2,
                     )
             else:
                 warn(
                     f"Child is a cameraprotocol which needs to be implemented {child_info}",
-                    stacklevel=1,
+                    stacklevel=2,
                 )
         # Replace parent child infos with the infos from the child fixtures so
         # that updates update both
@@ -223,7 +223,7 @@ class FakeSmartTransport(BaseTransport):
         if device_id not in self.child_protocols:
             warn(
                 f"Could not find child fixture {device_id} in {self.fixture_name}",
-                stacklevel=1,
+                stacklevel=2,
             )
             return self._handle_control_child_missing(params)