hush pyflakes warnings

src/allmydata/codec.py

@@ -4,7 +4,7 @@ from zope.interface import implements
 from twisted.internet import defer
 import sha
 from allmydata.util import idlib, mathutil
-from allmydata.util.assertutil import _assert, precondition
+from allmydata.util.assertutil import precondition
 from allmydata.interfaces import ICodecEncoder, ICodecDecoder
 import fec
 

src/allmydata/test/test_codec.py

@@ -1,5 +1,5 @@
 
-import os, time
+import os
 from twisted.trial import unittest
 from twisted.internet import defer
 from twisted.python import log

src/allmydata/test/trial_figleaf.py

@@ -60,7 +60,6 @@ from twisted.trial.reporter import TreeReporter, VerboseTextReporter
 # finish in printSummary.
 
 from allmydata.util import figleaf
-import os
 figleaf.start()