Pandas Feature Request: apply method to Index objects

I recently started using apply on my DataFrames and Series. It would be awesome to have this functionality on Index objects. I usually have to rename my indices a lot.

D_obsv_meta = dict(of-label-mapping)
DF_raw.index.apply(lambda x: D_obsv_meta[x])

Comment From: jreback

its called map (on Series) as well

In [3]: pd.Index(['foo', 'bar']).map(lambda x: {'foo':1, 'bar':2}[x])
Out[3]: array([1, 2], dtype=int64)