Fix conditional imports horked during unwind.

BTrees/IFBTree.py

@@ -137,7 +137,7 @@ except ImportError:
 
 weightedUnionPy = _setop(_weightedUnion, IFSetPy)
 try:
-    from _OIBTree import union
+    from _OIBTree import weightedUnion
 except ImportError:
     weightedUnion = weightedUnionPy
 

BTrees/IIBTree.py

@@ -137,13 +137,13 @@ except ImportError:
 
 weightedUnionPy = _setop(_weightedUnion, IISetPy)
 try:
-    from _OIBTree import union
+    from _IIBTree import weightedUnion
 except ImportError:
     weightedUnion = weightedUnionPy
 
 weightedIntersectionPy = _setop(_weightedIntersection, IISetPy)
 try:
-    from _OIBTree import weightedIntersection
+    from _IIBTree import weightedIntersection
 except ImportError:
     weightedIntersection = weightedIntersectionPy
 

BTrees/LFBTree.py

@@ -137,7 +137,7 @@ except ImportError:
 
 weightedUnionPy = _setop(_weightedUnion, LFSetPy)
 try:
-    from _OIBTree import union
+    from _OIBTree import weightedUnion
 except ImportError:
     weightedUnion = weightedUnionPy
 

BTrees/LLBTree.py

@@ -137,13 +137,13 @@ except ImportError:
 
 weightedUnionPy = _setop(_weightedUnion, LLSetPy)
 try:
-    from _OIBTree import union
+    from _LLBTree import weightedUnion
 except ImportError:
     weightedUnion = weightedUnionPy
 
 weightedIntersectionPy = _setop(_weightedIntersection, LLSetPy)
 try:
-    from _OIBTree import weightedIntersection
+    from _LLBTree import weightedIntersection
 except ImportError:
     weightedIntersection = weightedIntersectionPy
 

BTrees/OLBTree.py

@@ -130,7 +130,7 @@ except ImportError:
 
 weightedUnionPy = _setop(_weightedUnion, OLSetPy)
 try:
-    from _OLBTree import union
+    from _OLBTree import weightedUnion
 except ImportError:
     weightedUnion = weightedUnionPy