如何删除python pandas.DataFrame 的多重index

如下dataframe想要删除多层index

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print?

1. top1000[:10]  

			name	sex	births	year	prop
year	sex
1880	F	0	Mary	F	7065	1880	0.077643
		1	Anna	F	2604	1880	0.028618
		2	Emma	F	2003	1880	0.022013
		3	Elizabeth	F	1939	1880	0.021309
		4	Minnie	F	1746	1880	0.019188
		5	Margaret	F	1578	1880	0.017342
		6	Ida	F	1472	1880	0.016177
		7	Alice	F	1414	1880	0.015540
		8	Bertha	F	1320	1880	0.014507
		9	Sarah	F	1288	1880	0.014155

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print?

1. top1000.index = top1000.index.droplevel()  
2. top1000.index = top1000.index.droplevel()  
3. top1000[:10]  

	name	sex	births	year	prop
0	Mary	F	7065	1880	0.077643
1	Anna	F	2604	1880	0.028618
2	Emma	F	2003	1880	0.022013
3	Elizabeth	F	1939	1880	0.021309
4	Minnie	F	1746	1880	0.019188
5	Margaret	F	1578	1880	0.017342
6	Ida	F	1472	1880	0.016177
7	Alice	F	1414	1880	0.015540
8	Bertha	F	1320	1880	0.014507
9	Sarah	F	1288	1880	0.014155

Out[484]:

	name	sex	births	year	prop
0	Mary	F	7065	1880	0.077643
1	Anna	F	2604	1880	0.028618
2	Emma	F	2003	1880	0.022013
3	Elizabeth	F	1939	1880	0.021309
4	Minnie	F	1746	1880	0.019188
5	Margaret	F	1578	1880	0.017342
6	Ida	F	1472	1880	0.016177
7	Alice	F	1414	1880	0.015540
8	Bertha	F	1320	1880	0.014507
9	Sarah	F	1288	1880	0.014155