follow pep8 None should be compared using is or is not

http://legacy.python.org/dev/peps/pep-0008/
## Programming Recommendations
- Comparisons to singletons like None should always be done with is or is not, never the equality operators.

Author: Ken Takagiwa <ken@Kens-MacBook-Pro.local>

Closes #1422 from giwa/apache_master and squashes the following commits:

7b361f3 [Ken Takagiwa] follow pep8 None should be checked using is or is not

1 files changed, 2 insertions, 2 deletions

diff --git a/python/pyspark/conf.py b/python/pyspark/conf.py
index 8eff4a242a..60fc6ba7c5 100644
--- a/python/pyspark/conf.py
+++ b/python/pyspark/conf.py
@@ -30,7 +30,7 @@ u'My app'
 u'local'
 >>> sc.appName
 u'My app'
->>> sc.sparkHome == None
+>>> sc.sparkHome is None
 True
 
 >>> conf = SparkConf(loadDefaults=False)
@@ -116,7 +116,7 @@ class SparkConf(object):
 
     def setExecutorEnv(self, key=None, value=None, pairs=None):
         """Set an environment variable to be passed to executors."""
-        if (key != None and pairs != None) or (key == None and pairs == None):
+        if (key is not None and pairs is not None) or (key is None and pairs is None):
             raise Exception("Either pass one key-value pair or a list of pairs")
         elif key != None:
             self._jconf.setExecutorEnv(key, value)