This snippet will give you an idea on how to sort values when it is in the group

sort_grouped.py

'''
State     District      Population(values)

Guj       Kutch         30
          Ahmedabad     100
          Surat         50
          Vadodra       20
          Jak           10
          
Maha      Mumbai        130
          Borri         10
          Pune          150
          
UP        Patna         20
          Gorakhpur     50
          Luckhnow      500
'''
# Having this... if we need to sort in the group itself...
DF.sort_values()
# ↑ This will scramble all values

## THIS IS THE ONE ↓ ##
DF.sort_values().sort_index(index= 0, sort_remaining= False)
                          # ↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑
                          # This part is so useful - Do it!