Index: pyyaml/trunk/lib/yaml/constructor.py
===================================================================
--- pyyaml/trunk/lib/yaml/constructor.py	(revision 234)
+++ pyyaml/trunk/lib/yaml/constructor.py	(revision 235)
@@ -13,5 +13,5 @@
     from sets import Set as set
 
-import binascii, re, sys
+import binascii, re, sys, types
 
 class ConstructorError(MarkedYAMLError):
@@ -37,8 +37,4 @@
         if self.check_node():
             return self.construct_document(self.get_node())
-
-    def g(): yield None
-    generator_type = type(g())
-    del g
 
     def construct_document(self, node):
@@ -92,5 +88,5 @@
         else:
             data = constructor(self, tag_suffix, node)
-        if isinstance(data, self.generator_type):
+        if isinstance(data, types.GeneratorType):
             generator = data
             data = generator.next()