我有一个数据是：https://github.com/mayuripandey/Data-Analysis/blob/main/Topic.csv，
例如：

Topic1_assignment                              |             Topic2_assignment
0   Int64Index([ 0, 1, 3, 7, 8, 11], dtype='int64    |  Int64Index([ 0, 4, 5, 9, 11, 14], dtype='int64)
1   NaN                                              | Int64Index([ 0, 2, 5, 7, 10, 14], dtype='int64)
2   Int64Index([ 0, 1, 2, 210, 219, 221], dtype='int64') |. Int64Index([ 256, 257, 258, 259, 260, 261], dtype='int64)

在这里我试图找到两个包含NaN值的列表的交集。
我使用的代码是：

df9['c'] = [len(set(a).intersection(b)) if all(pd.notna([a, b])) else 0
                for a, b in zip(df9.Topic1_assignment, df9.Topic2_assignment)],

但它给出了一个错误：

---------------------------------------------------------------------------
ValueError                                Traceback (most recent call last)
<ipython-input-65-af99ddc88358> in <module>
----> 1 df9['c'] = [len(set(a).intersection(b)) if all(pd.notna([a, b])) else 0
      2                 for a, b in zip(df9.Topic1_assignment, df9.Topic2_assignment)]

<ipython-input-65-af99ddc88358> in <listcomp>(.0)
----> 1 df9['c'] = [len(set(a).intersection(b)) if all(pd.notna([a, b])) else 0
      2                 for a, b in zip(df9.Topic1_assignment, df9.Topic2_assignment)]

ValueError: The truth value of an array with more than one element is ambiguous. Use a.any() or a.all().

可能的原因是什么？