Fix pep8 job

New flake8 came out with new & improved rules. Ignore E741; it would be
too much churn. Fix the rest.

Change-Id: I9125c8c53423232309a75cbcc5b695b378864c1b

swift/cli/ringbuilder.py

@@ -1658,7 +1658,7 @@ def main(arguments=None):
         print(msg)
         exit(EXIT_ERROR)
     except (exceptions.FileNotFoundError, exceptions.PermissionError) as e:
-        if len(argv) < 3 or argv[2] not in('create', 'write_builder'):
+        if len(argv) < 3 or argv[2] not in ('create', 'write_builder'):
             print(e)
             exit(EXIT_ERROR)
     except Exception as e:

test/unit/common/ring/test_builder.py

@@ -2113,7 +2113,7 @@ class TestRingBuilder(unittest.TestCase):
         orig_rb = ring.RingBuilder(8, 3, 1)
         copy_rb = ring.RingBuilder(8, 3, 1)
         copy_rb.copy_from(orig_rb)
-        for rb in(orig_rb, copy_rb):
+        for rb in (orig_rb, copy_rb):
             with self.assertRaises(AttributeError) as cm:
                 rb.id
             self.assertIn('id attribute has not been initialised',

test/unit/common/test_db.py

@@ -1289,7 +1289,7 @@ class TestDatabaseBroker(unittest.TestCase):
         for c in range(MAX_META_COUNT):
             key = 'X-Account-Meta-F{0}'.format(c)
             metadata[key] = ('B', normalize_timestamp(1))
-        key = 'X-Account-Meta-Foo'.format(c)
+        key = 'X-Account-Meta-Foo'
         metadata[key] = ('', normalize_timestamp(1))
         self.assertIsNone(DatabaseBroker.validate_metadata(metadata))
 

tox.ini

@@ -143,10 +143,11 @@ commands = bandit -c bandit.yaml -r swift -n 5
 # changes to enable:
 # E402: module level import not at top of file
 # E731 do not assign a lambda expression, use a def
+# E741 ambiguous variable name
 # Swift team needs to decide if they want to enable either of these:
 # W503: line break before binary operator
 # W504: line break after binary operator
-ignore = H101,H202,H301,H306,H404,H405,H501,W503,W504,E402,E731
+ignore = H101,H202,H301,H306,H404,H405,H501,W503,W504,E402,E731,E741
 exclude = .venv,.tox,dist,*egg
 filename = *.py,bin/*
 show-source = True