Fix pep8 on Python3.5

This patch is fixing the pep8 warning messages when running "tox -epep8"
with the python3.5 interpreter (the default on some distros, e.g Arch
Linux).

The method file_open() from common/utils.py was removed because it
wasn't being used anywhere and was violating pep8 by using file() which
is only present in python2.

Change-Id: Ie9356a870ea7b271aa44db57accba02f52b3e948
Closes-Bug: #1617947

devstack/tools/ironic/scripts/configure-vm.py

@@ -80,7 +80,7 @@ def main():
     parser.add_argument('--disk-format', default='qcow2',
                         help='Disk format to use.')
     args = parser.parse_args()
-    with file(templatedir + '/vm.xml', 'rb') as f:
+    with open(templatedir + '/vm.xml', 'rb') as f:
         source_template = f.read()
     params = {
         'name': args.name,

ironic/common/exception.py

@@ -78,13 +78,13 @@ class IronicException(Exception):
     def __str__(self):
         """Encode to utf-8 then wsme api can consume it as well."""
         if not six.PY3:
-            return unicode(self.args[0]).encode('utf-8')
+            return six.text_type(self.args[0]).encode('utf-8')
 
         return self.args[0]
 
     def __unicode__(self):
         """Return a unicode representation of the exception message."""
-        return unicode(self.args[0])
+        return six.text_type(self.args[0])
 
 
 class NotAuthorized(IronicException):

ironic/common/utils.py

@@ -372,18 +372,6 @@ def read_cached_file(filename, cache_info, reload_func=None):
     return cache_info['data']
 
 
-def file_open(*args, **kwargs):
-    """Open file
-
-    see built-in file() documentation for more details
-
-    Note: The reason this is kept in a separate module is to easily
-          be able to provide a stub module that doesn't alter system
-          state at all (for unit tests)
-    """
-    return file(*args, **kwargs)
-
-
 def _get_hash_object(hash_algo_name):
     """Create a hash object based on given algorithm.
 

ironic/tests/unit/api/v1/test_types.py

@@ -285,9 +285,8 @@ class TestJsonType(base.TestCase):
     def test_apimultitype_tostring(self):
         vts = str(types.jsontype)
         self.assertIn(str(wtypes.text), vts)
-        self.assertIn(str(int), vts)
-        if six.PY2:
-            self.assertIn(str(long), vts)
+        for int_type in six.integer_types:
+            self.assertIn(str(int_type), vts)
         self.assertIn(str(float), vts)
         self.assertIn(str(types.BooleanType), vts)
         self.assertIn(str(list), vts)

ironic/tests/unit/common/test_exception.py

@@ -23,8 +23,6 @@ class TestIronicException(base.TestCase):
         expected = b'\xc3\xa9\xe0\xaf\xb2\xe0\xbe\x84'
         if six.PY3:
             expected = expected.decode('utf-8')
-            message = chr(233) + chr(0x0bf2) + chr(3972)
-        else:
-            message = unichr(233) + unichr(0x0bf2) + unichr(3972)
+        message = six.unichr(233) + six.unichr(0x0bf2) + six.unichr(3972)
         exc = exception.IronicException(message)
         self.assertEqual(expected, exc.__str__())