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
https://issues.apache.org/jira/browse/SPARK-1917
Author: Uri Laserson <laserson@cloudera.com>
Closes#866 from laserson/SPARK-1917 and squashes the following commits:
d947e8c [Uri Laserson] Added test for scipy.special importing
1798bbd [Uri Laserson] SPARK-1917: fix PySpark import of scipy.special