Style cleanup in auxiliary bisect-related scripts.

tools/prepare-bisect-perf-regression.py

Index: tools/prepare-bisect-perf-regression.py
diff --git a/tools/prepare-bisect-perf-regression.py b/tools/prepare-bisect-perf-regression.py
index 3c57ce50d08dad01d5a453410ee4ce0e963a117d..9ead957ac13bfc5db9d5d95b1c48940e9b697265 100755
--- a/tools/prepare-bisect-perf-regression.py
+++ b/tools/prepare-bisect-perf-regression.py
@@ -15,7 +15,6 @@ An example usage:
 
 Would result in creating ~/builds/bisect and then populating it with a copy of
 the depot.
-
 """
 
 import optparse
@@ -25,6 +24,7 @@ from auto_bisect import bisect_utils
 
 
 def main():
+  """Does an initial checkout of Chromium then exits."""
 
   usage = ('%prog [options] [-- chromium-options]\n'
            'Prepares a temporary depot for use on a trybot.')
@@ -39,7 +39,7 @@ def main():
                     'working_directory and that will be used to perform the '
                     'bisection.')
   parser.add_option('--output_buildbot_annotations',
-                    action="store_true",
+                    action='store_true',
                     help='Add extra annotation output for buildbot.')
   parser.add_option('--target_platform',
                     type='choice',
@@ -49,7 +49,7 @@ def main():
                     'platform), "cros", or "android". If you specify something '
                     'other than "chromium", you must be properly set up to '
                     'build that platform.')
-  (opts, args) = parser.parse_args()
+  opts, _ = parser.parse_args()
 
   if not opts.working_directory:
     print 'Error: missing required parameter: --working_directory'
@@ -59,8 +59,8 @@ def main():
 
   if not bisect_utils.CheckIfBisectDepotExists(opts):
     try:
-      bisect_utils.CreateBisectDirectoryAndSetupDepot(opts,
-          bisect_utils.DEFAULT_GCLIENT_CUSTOM_DEPS)
+      bisect_utils.CreateBisectDirectoryAndSetupDepot(
+          opts, bisect_utils.DEFAULT_GCLIENT_CUSTOM_DEPS)
     except RuntimeError:
       return 1
   return 0