Fix namespace bug in write_directory_tree(max_manifest_depth=0).

diff --git a/sdk/python/arvados/collection.py b/sdk/python/arvados/collection.py
index ff29919f1bf3c6a0e7e60245333ad454164f2df5..fb3dea43acc6872d11ccdbc5456c2d87e5c15c73 100644 (file)
--- a/sdk/python/arvados/collection.py
+++ b/sdk/python/arvados/collection.py
@@ -22,6 +22,7 @@ from keep import *
 from stream import *
 import config
 import errors
+import util
 
 def normalize_stream(s, stream):
     stream_tokens = [s]