switch to context manager

api/src/opentrons/protocol_api/instrument_context.py

@@ -539,16 +539,12 @@ def mix(
             ),
         ):
             self.aspirate(volume, location, rate)
-            if self.api_version >= APIVersion(2, 20):
-                auto_presence = self.liquid_presence_detection
-                self.liquid_presence_detection = False
-            while repetitions - 1 > 0:
-                self.dispense(volume, rate=rate, **dispense_kwargs)
-                self.aspirate(volume, rate=rate)
-                repetitions -= 1
-            self.dispense(volume, rate=rate)
-            if self.api_version >= APIVersion(2, 20):
-                self.liquid_presence_detection = auto_presence
+            with AutoProbeDisable(self):
+                while repetitions - 1 > 0:
+                    self.dispense(volume, rate=rate, **dispense_kwargs)
+                    self.aspirate(volume, rate=rate)
+                    repetitions -= 1
+                self.dispense(volume, rate=rate)
         return self
 
     @requires_version(2, 0)
@@ -2195,6 +2191,22 @@ def _raise_if_configuration_not_supported_by_pipette(
             # SINGLE, QUADRANT and ALL are supported by all pipettes
 
 
+class AutoProbeDisable:
+    """Use this class to temporarily disable automatic liquid presence detection."""
+
+    def __init__(self, instrument: InstrumentContext):
+        self.instrument = instrument
+
+    def __enter__(self) -> None:
+        if self.instrument.api_version >= APIVersion(2, 20):
+            self.auto_presence = self.instrument.liquid_presence_detection
+            self.instrument.liquid_presence_detection = False
+
+    def __exit__(self, *args: Any, **kwargs: Any) -> None:
+        if self.instrument.api_version >= APIVersion(2, 20):
+            self.instrument.liquid_presence_detection = self.auto_presence
+
+
 def _raise_if_has_end_or_front_right_or_back_left(
     style: NozzleLayout,
     end: Optional[str],