six: sparql aggregates no longer relies on map returning a list

the types variable became an iterable and was exhausted on 2nd check in py3

Author: joernhees

rdflib/plugins/sparql/aggregates.py

@@ -72,8 +72,10 @@ def use_row(self, row):
 
 
 def type_safe_numbers(*args):
-    types = map(type, args)
-    if float in types and Decimal in types:
+    if (
+            any(isinstance(arg, float) for arg in args)
+            and any(isinstance(arg, Decimal) for arg in args)
+    ):
         return map(float, args)
     return args