patched logging config.

zipline/finance/performance.py

@@ -114,8 +114,6 @@ Performance Period
 import logging
 import datetime
 import pytz
-import msgpack
-import pandas
 import math
 
 import zmq

zipline/logging.cfg

@@ -20,7 +20,7 @@ qualname=ZiplineLogger
 class=handlers.RotatingFileHandler
 level=DEBUG
 formatter=ziplineformat
-args=("/var/log/zipline/zipline.log",10*1024*1024,5)
+args=("/var/log/zipline/zipline.log",'a',10*1024*1024,5)
 propagate=1
 
 [handler_consoleHandler]