[cli] adds python logging facility configuration.

bonobo/util/iterators.py

@@ -1,4 +1,5 @@
 """ Iterator utilities. """
+import functools
 
 
 def force_iterator(mixed):
@@ -20,7 +21,20 @@ def force_iterator(mixed):
 def ensure_tuple(tuple_or_mixed):
     if isinstance(tuple_or_mixed, tuple):
         return tuple_or_mixed
-    return (tuple_or_mixed, )
+    return (tuple_or_mixed,)
+
+
+def tuplize(generator):
+    """ Takes a generator and make it a tuple-returning function. As a side
+    effect, it can also decorate any iterator-returning function to force
+    return value to be a tuple.
+    """
+
+    @functools.wraps(generator)
+    def tuplized(*args, **kwargs):
+        return tuple(generator(*args, **kwargs))
+
+    return tuplized
 
 
 def iter_if_not_sequence(mixed):