[Python] How to convert index of a pandas dataframe into a column

How to convert an index of a dataframe into a column?

For example:

gi ptt_loc
0 384444683 593
1 384444684 594
2 384444686 596


to

index1 gi ptt_loc
0 0 384444683 593
1 1 384444684 594
2 2 384444686 596

Continue reading...