avoid circular import

Author: slayoo

PySDM/attributes/impl/temperature_variation_option_attribute.py

@@ -1,14 +1,12 @@
 """common code for attributes offering an option to neglect temperature variation,
 intended for use with Parcel environment only"""
 
-from PySDM.environments import Parcel
-
 
 class TemperatureVariationOptionAttribute:  # pylint: disable=too-few-public-methods
     """base class"""
 
     def __init__(self, builder, neglect_temperature_variations: bool):
-        assert isinstance(builder.particulator.environment, Parcel)
+        assert builder.particulator.environment.__class__.__name__ == "Parcel"
         self.neglect_temperature_variations = neglect_temperature_variations
         self.initial_temperature = builder.particulator.Storage.from_ndarray(
             builder.particulator.environment["T"].to_ndarray()