.ix indexing can't handle duplicate index values
```
(Pdb) result
      A   B   C   D
foo   2   3   4   5
bar   7   8   9  10
baz  12  13  14  15
qux  12  13  14  15
foo  12  13  14  15
bar  12  13  14  15
(Pdb) result.ix['bar']
*** Exception: Reindexing only valid with uniquely valued Index objects
```
