在数据混合的csv中，如何正确分隔两列？

Question

我希望所有JEL分类都在一列（称为classification）中，关键字在另一列（称为keywords）中，示例数据如下。这里k/c是第一列c/k是下一列

                                                 k/c  \
0  Keywords\r\nLegal systemsInstitutional environ...   
1                       JEL classification\r\nG30G34   
2                JEL classifications\r\nG38J21J30P26   
3         JEL classification codes\r\nG30G34G38K21L4   
4                       JEL classification\r\nG11G23   
5                                                NaN   
6                                                NaN   
7                                                NaN   
8                                                NaN   
9                      JEL classifications\r\nG24G23   

                                                 c/k  
0                 JEL classification\r\nG21G24G32G34  
1  Keywords\r\nDirector electionsFamily firmsGove...  
2  Keywords\r\nPolitical connection disruptionsLa...  
3  Keywords\r\nMergers and acquisitions (M&A)Acqu...  
4  Keywords\r\nAdvisory ratesFund governanceAgenc...  
5  Keywords\r\nHometown connectionsTrade creditCE...  
6                                                NaN  
7  Keywords\r\nOperating riskInvestment riskCredi...  
8                                                NaN  
9  Keywords\r\nHerd behaviourBuyoutPrivate equity... 

df["classification"] = []
df["keywords"] = []

for i in df[["k/c"]]:
    if i == Keywords:
        df["keywords"].append(i)
    elif i == JEL:
        df["classification"].append(i)

print(["classification"])
print(["keywords"])