Fixed deprecated import

Joel Collins · Joel Collins · commit 8c183f9074eb · 2020-04-09T13:02:10.000+01:00
diff --git a/labthings/server/spec/utilities.py b/labthings/server/spec/utilities.py
@@ -6,7 +6,7 @@
 from ..fields import Field
 from marshmallow import Schema as BaseSchema
 
-from collections import Mapping
+from collections.abc import Mapping
 
 
 def update_spec(obj, spec: dict):
