3603: Clean up PySDK imports.

[arvados.git] / sdk / python / arvados / collection.py

diff --git a/sdk/python/arvados/collection.py b/sdk/python/arvados/collection.py
index 390ed3b3afeb4922c81ec48682b1c6a81206e641..59dc49fbbc8fbcb21107f8cfca61c40bf6176a7a 100644 (file)
--- a/sdk/python/arvados/collection.py
+++ b/sdk/python/arvados/collection.py
@@ -1,22 +1,6 @@
-import gflags
-import httplib
-import httplib2
 import logging
 import os
-import pprint
-import sys
-import types
-import subprocess
-import json
-import UserDict
 import re
-import hashlib
-import string
-import bz2
-import zlib
-import fcntl
-import time
-import threading
 
 from collections import deque
 from stat import *
@@ -71,9 +55,9 @@ def normalize_stream(s, stream):
 
 class CollectionBase(object):
     def __enter__(self):
-        pass
+        return self
 
-    def __exit__(self):
+    def __exit__(self, exc_type, exc_value, traceback):
         pass
 
     def _my_keep(self):
@@ -290,8 +274,9 @@ class CollectionWriter(CollectionBase):
         self._queued_dirents = deque()
         self._queued_trees = deque()
 
-    def __exit__(self):
-        self.finish()
+    def __exit__(self, exc_type, exc_value, traceback):
+        if exc_type is None:
+            self.finish()
 
     def do_queued_work(self):
         # The work queue consists of three pieces: