DataFrame.sort_values(by, axis=0, ascending=True, inplace=False, kind='quicksort', na_position='last')
df.sort_values(by='col1' / ['col1'], axis=0) # sort by col1
df.sort_values(by=['co1', 'col2']) # sort by col1, then by col2
df.sort_values(by=*, ascending=False) # sort descending
df.sort_values(by=*, na_position='first') # Putting NAs first