diff --git a/image_prediction/formatter/formatters/camel_case.py b/image_prediction/formatter/formatters/camel_case.py
index 228baa4..bb6cd9d 100644
--- a/image_prediction/formatter/formatters/camel_case.py
+++ b/image_prediction/formatter/formatters/camel_case.py
@@ -19,7 +19,8 @@ class Snake2CamelCaseKeyFormatter(Formatter):
         # If we wanted to do this properly, we would need handlers for all expected types and dispatch based
         # on a type comparison. This is too much engineering for the limited use-case of this class though.
         if isinstance(data, Iterable) and not isinstance(data, dict) and not isinstance(data, str):
-            return type(data)(map(self.__format, data))
+            f = map(self.__format, data)
+            return type(data)(f) if not isinstance(data, map) else f
 
         if not isinstance(data, dict):
             return data