Python 熊猫：比较数据框的列并添加新列&；基于条件的值

我有一个数据框

ip_df:
     name class    sec    details
0    tom  I        a      [{'class':'I','sec':'a','subjects':['numbers','ethics']},{'class':'I','sec':'b','subjects':['numbers','moral-science']},{'class':'I','sec':'c','subjects':['moral-science','ethics']},{'class':'I','subjects':['numbers','ethics1']}]
1    sam  I        d      [{'class':'I','sec':'a','subjects':['numbers','ethics']},{'class':'I','sec':'b','subjects':['numbers','moral-science']},{'class':'I','sec':'c','subjects':['moral-science','ethics']},{'class':'I','subjects':['numbers','ethics1']}] 

假设得到的数据帧是

op_df:
      name  class  sec   subjects
0     tom   I      a     ['numbers','ethics']
1     sam   I      d     ['numbers','ethics1']

“op_df”必须基于以下条件进行框定：

• 条件1：检查“详细信息”列中是否存在“类”和“秒”，如果存在，请添加一个名为“主题”的新列及其相应的值
• 条件2：如果“详细信息”列中不存在“类”和“秒”，请检查“类”是否匹配，如果匹配，请添加一个名为“主题”的新列及其相应的值
• 如果条件1和条件2都不存在，则在“主题”列中添加默认值[0,0]

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解决方案，如果需要通过两种条件首先匹配值，则使用

next

和

iter

技巧添加默认值

[0,0]

如果不匹配：

final = []
for a, b, c in zip(df['class'], df['sec'], df['details']):
    out = []
    for x in c:
        m1 = x['class'] == a 
        if m1 and x.get('sec') == b:
            out.append(x['subjects'])
        elif m1 and 'sec' not in list(x.keys()):
            out.append(x['subjects'])
    final.append(next(iter(out), [0,0]))

df['subjects'] =  final

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你试过什么？你面临的问题是什么？我们应该帮你做什么？