fix some hints from flake8

bench.py

@@ -30,10 +30,10 @@ parser.add_argument("-rd", "--resultdir", help="directory where all results go",
 parser.add_argument("--license", help="print license info and exit", action='store_true')
 
 
-"""Run tasks on exit"""
 def epilog():
+    """Run tasks on exit"""
     # After early errors resdir may not be set
-    if src.globalvars.resdir != None:
+    if src.globalvars.resdir is not None:
         if os.listdir(src.globalvars.resdir) == []:
             print_warn("Remove empty resultdir")
             os.removedirs(src.globalvars.resdir)
@@ -44,6 +44,7 @@ def epilog():
             with open(os.path.join(src.globalvars.resdir, "facts.save"), "wb") as f:
                 pickle.dump(src.globalvars.facts, f)
 
+
 def main():
     args = parser.parse_args()
     if args.license:
@@ -138,7 +139,7 @@ def main():
 
     cwd = os.getcwd()
     for bench in src.globalvars.benchmarks:
-        if args.benchmarks and not bench in args.benchmarks:
+        if args.benchmarks and bench not in args.benchmarks:
             continue
 
         if args.analyse or not args.nosum:
@@ -160,7 +161,6 @@ def main():
                 if find_cmd("malt") is not None:
                     print_status("Analysing {} ...".format(bench))
 
-
                     malt_cmd = "malt -o output:name={}/malt.{}.%3"
                     malt_cmd = malt_cmd.format(bench_res_dir, "{perm}")