Sorting Months inside a Multi index groupby object

Its the sample input. i wanted to group according to the Year column,and wanted to use value counts on month column, then to sort the 'month' column according to the month order.

I did this: df.groupby(['Year'])['month'].value_counts() i got the following output:

now i need to sort the month in the original month order.what can i do? i want the following output:

You can use groupby() and sort_values(by=['Year', 'month']):

import pandas as pd


def _sort_month(df):
    month_order = ['Jan', 'Feb', 'Mar', 'Apr', 'May', 'Jun', 'Jul', 'Aug', 'Sep', 'Oct', 'Nov', 'Dec']
    df['month'] = pd.Categorical(df['month'], categories=month_order, ordered=True)
    GB = df.groupby(['Year'])['month'].value_counts()
    G = GB.reset_index(name='count')
    res = G.sort_values(by=['Year', 'month'])
    res.set_index(['Year', 'month'], inplace=True)
    return res[res['count'] > 0]


df = pd.DataFrame({'Year': [2000, 2002, 2002, 2000, 2002, 2000],
                   'month': ['Oct', 'Jan', 'Mar', 'Oct', 'Mar', 'Jan']})

print(_sort_month(df))

Prints

            count
Year month       
2000 Jan        1
     Oct        2
2002 Jan        1
     Mar        2