BUG: fix data.py regression
BUG: Fixed non-unique indexing memory allocation issue with .ix/.loc (GH4280)
Merge pull request #4283 from jreback/index_mem

BUG: Fixed non-unique indexing memory allocation issue with .ix/.loc (GH4280)
Merge pull request #4281 from cpcloud/data-py-regression-fix

BUG: fix data.py regression