I have two lists
list1 = ['B', 'C', 'D'] list2 = [['1', 'A'], ['2', 'B'], ['3', 'D'], ['5', 'C']]
and want to return those sublistst of list2 that contain elements of list1. So far I tried using any:
result = []
for l2 in list2:
    if any (item in l2 for item in list1):
        result.append(l2)
and a naive approach
for l2 in list2:
    for l1 in l1:
        if l1 in l2:
            result.append(l2)
But I only managed to repeat empty list. The result should be
result = [['2', 'B'], ['5', 'C']]
Not sure, where I’m going wrong. Is there maybe a way using list comprehensions or mixing list comprehensions and ‘any’ function?
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Answer
What you have looks correct and works for me locally too:
for l2 in list2:
    if any (item in l2 for item in list1):
        result.append(l2)
It returns [['2', 'B'], ['3', 'D'], ['5', 'C']] which is the expected result right?
Also note that you can speed up your implementation by changing list1 into a set list1 = set(['B', 'C', 'D']) and changing the if condition to  if any (item in list1 for item in l2):.
This is because item in list1 is much faster if list1 is a set than a list. That’s because set uses a hashmap under the hood the quickly accesss elements.