1In [194]: df.reset_index(drop=True)
2Out[194]:
3 _worker_id foo
40 A 1
51 B 2
62 C 3
1>>> df.reset_index()
2 index class max_speed
30 falcon bird 389.0
41 parrot bird 24.0
52 lion mammal 80.5
63 monkey mammal NaN
7