``` python In [2]: import pandas In [3]: df0 = pandas.DataFrame([[10, 20, 30], [10, 20, 30], [10, 20, 30]]) df0 Out [3]: 0 1 2 0 10 20 30 1 10 20 30 2 10 20 30 In [4]: pandas.concat(dict(a=None, b=df0, c=df0[:2], d=df0[:1], e=df0)) Out [4]: 0 1 2 a 0 10 20 30 1 10 20 30 2 10 20 30 b 0 10 20 30 1 10 20 30 c 0 10 20 30 d 0 10 20 30 1 10 20 30 2 10 20 30 ``` Checked with the current master e1129b11b1fe0016748d3d279000a2a71db8dee5 and 0.7.3