Return status of called method.

Also remove not needed imports.

src/zc/buildout/networkcache.py

@@ -17,8 +17,6 @@ import hashlib
 import os
 import posixpath
 import re
-import urllib
-import urlparse
 
 try:
     from slapos.libnetworkcache import NetworkcacheClient, UploadError, \
@@ -113,7 +111,7 @@ def upload_network_cached(dir_url, cache_url, external_url, path, logger):
     try:
         nc = NetworkcacheClient(shacache=cache_url,
                                 shadir=dir_url)
-        data = nc.upload(f, directory_key, **kw)
+        return nc.upload(f, directory_key, **kw)
     except (IOError, UploadError), e:
         logger.info('Fail to upload file. %s' % \
                                                   (str(e)))