我有一个包含国际贸易统计数据的数据框，该数据框根据协调的关税代码分为四个层次。级别1是1,2或3。级别2有2位数字，依此类推，级别4有4位数字。
我想按三级的特定代码进行过滤，并查看数据中所有四级项的分组汇总
filCode=df['Level3Code']=='242'
[filCode].groupby('Level4')['Total Exports'].sum().sort_values(ascending=False)
I'm expecting to see the following level four codes together with totals value sums for each code
'2421 Pharmaceutical products' sum for this category
'2422 Essential oils perfume & cosmetic products' sum for this category
'2423 Plastics & articles of plastic' sum for this category
'2424 Other chemical & chemical preparations elaborately transformed' sum for this category
'2425 Other semi-manufactures elaborately transformed sum for this category
相反，我看到的是按照应该被过滤掉的类别计算的一堆总计...。因此：
T4
2421 Pharmaceutical products 3.983
2424 Other chemical & chemical preparations elaborately transformed 2.084
2422 Essential oils perfume & cosmetic products 1.068
2423 Plastics & articles of plastic 0.742
2425 Other semi-manufactures elaborately transformed 0.393
...
2313 Non-ferrous metals simply transformed 0.000
2312 Iron & steel simply transformed 0.000
2311 Non-metallic mineral manufactures simply transformed 0.000
3021 Non-monetary gold 0.000
1111 Live animals chiefly for food 0.000
Name: Total Exports, Length: 61, dtype: float64