*: Fix pyflakes warnings

diff --git a/tornado/gen.py b/tornado/gen.py
index 0ce4dc9f2bf62337759ffc294b0464ed7d34a4a9..99f9106666b59b6d5282c47cc63b8f43f405c3b0 100644 (file)
--- a/tornado/gen.py
+++ b/tornado/gen.py
@@ -1147,7 +1147,8 @@ class Runner(object):
 
         if not self.future.done() or self.future is moment:
             def inner(f):
-                f = None
+                # Break a reference cycle to speed GC.
+                f = None # noqa
                 self.run()
             self.io_loop.add_future(
                 self.future, inner)

diff --git a/tornado/log.py b/tornado/log.py
index f870da4aef9f74dd60ce828eaf9a8f86d17ea22d..01519177aada3a630d07170c6d6aed7c14a4b715 100644 (file)
--- a/tornado/log.py
+++ b/tornado/log.py
@@ -32,7 +32,6 @@ from __future__ import absolute_import, division, print_function
 
 import logging
 import logging.handlers
-import os
 import sys
 
 from tornado.escape import _unicode

diff --git a/tornado/websocket.py b/tornado/websocket.py
index 1668a596855f5d3d4587490af0ba5d990dd466f3..ce13d262b87a1af3210a51cd7791fe6d007f13f7 100644 (file)
--- a/tornado/websocket.py
+++ b/tornado/websocket.py
@@ -513,12 +513,12 @@ class _PerMessageDeflateCompressor(object):
                              max_wbits, zlib.MAX_WBITS)
         self._max_wbits = max_wbits
 
-        if compression_options is None or not 'compression_level' in compression_options:
+        if compression_options is None or 'compression_level' not in compression_options:
             self._compression_level = tornado.web.GZipContentEncoding.GZIP_LEVEL
         else:
             self._compression_level = compression_options['compression_level']
 
-        if compression_options is None or not 'mem_level' in compression_options:
+        if compression_options is None or 'mem_level' not in compression_options:
             self._mem_level = 8
         else:
             self._mem_level = compression_options['mem_level']
@@ -638,7 +638,6 @@ class WebSocketProtocol13(WebSocketProtocol):
             self.request.headers.get("Sec-Websocket-Key"))
 
     def _accept_connection(self):
-        subprotocol_header = ''
         subprotocols = self.request.headers.get("Sec-WebSocket-Protocol", '')
         subprotocols = [s.strip() for s in subprotocols.split(',')]
         if subprotocols:
@@ -647,7 +646,6 @@ class WebSocketProtocol13(WebSocketProtocol):
                 assert selected in subprotocols
                 self.handler.set_header("Sec-WebSocket-Protocol", selected)
 
-        extension_header = ''
         extensions = self._parse_extensions_header(self.request.headers)
         for ext in extensions:
             if (ext[0] == 'permessage-deflate' and