如何将pandas数据帧重新排列到此特定配置中？

import pandas as pd

df = pd.DataFrame({'A': ['foo', 'foo', 'foo', 'bar', 'bar', 'bar'],
                   'B': ['one', 'one', 'two', 'two', 'one', 'one'],
                   'C': ['x', 'y', 'x', 'y', 'x', 'y'],
                   'D': [1, 2, 3, 4, 5, 6]})

pivot_df = df.pivot(index='A', columns='B', values='D')

B    one  two
A            
bar    5    4
foo    1    3

import pandas as pd

df = pd.DataFrame({'A': ['foo', 'foo', 'foo', 'bar', 'bar', 'bar'],
                   'B': ['one', 'one', 'two', 'two', 'one', 'one'],
                   'C': ['x', 'y', 'x', 'y', 'x', 'y'],
                   'D': [1, 2, 3, 4, 5, 6]})

pivot_table_df = df.pivot_table(index='A', columns='B', values='D', aggfunc=sum)

B    one  two
A            
bar    11   4
foo    3    3

import pandas as pd

df = pd.DataFrame({'A': ['foo', 'foo', 'foo', 'bar', 'bar', 'bar'],
                   'B': ['one', 'one', 'two', 'two', 'one', 'one'],
                   'C': ['x', 'y', 'x', 'y', 'x', 'y'],
                   'D': [1, 2, 3, 4, 5, 6]})

melted_df = df.melt(id_vars=['A', 'B'], value_vars=['C', 'D'])

    A    B variable  value
0  foo  one        C      x
1  foo  one        C      y
2  foo  two        C      x
3  bar  two        C      y
4  bar  one        C      x
5  bar  one        C      y
6  foo  one        D      1
7  foo  one        D      2
8  foo  two        D      3
9  bar  two        D      4
10 bar  one        D      5
11 bar  one        D      6

import pandas as pd

df = pd.DataFrame({'A': ['foo', 'foo', 'foo', 'bar', 'bar', 'bar'],
                   'B': ['one', 'one', 'two', 'two', 'one', 'one'],
                   'C': ['x', 'y', 'x', 'y', 'x', 'y'],
                   'D': [1, 2, 3, 4, 5, 6]})

stacked_df = df.set_index(['A', 'B']).stack()
unstacked_df = stacked_df.unstack()

A    B   
foo  one  C      x
          D      1
     two  C      x
          D      3
bar  two  C      y
          D      4
     one  C      x
          D      5
dtype: object

B    one  two
A            
bar    5    4
foo    1    3