Pandas >> Index

# Prepare the data
import pandas as pd

df = pd.DataFrame({'A': ["a", "b", "c", "d"],
                   'B': [10, 20, 30, 40],
                   'C': [100, 200, 300, 400]})
df

df2 = df.reset_index()
# OR Directly change the df
df.reset_index(inplace=True)

df2 = df.reset_index().rename(columns={'index':'my_index'})
# OR 
df2 = df.reset_index()
df2.index.name = 'my_index'

df2

df2 = df.set_index('A')
df2

df2.index.name

df2.index.values

df2.index.tolist()

# Reset the index and add 1 to it to start from 0
df2.index = df2.reset_index().index + 1
df2

df2.idxmax()

df2.idxmax()["B"]

df2.loc[df2.idxmax()["B"]]