how to make the index a column in pandas code example

Example 1: pandas create a column from index

df.reset_index(level=0, inplace=True)

Example 2: how to make index column as a normal column

>>> df
                       val
tick       tag obs        
2016-02-26 C   2    0.0139
2016-02-27 A   2    0.5577
2016-02-28 C   6    0.0303