IndexError: list index out of range >>> python [duplicate]

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• Remove all the elements that occur in one list from another 6 answers

 a=['a','b','c','d']


 b=['l','b','n','d']


 for i in range(len(a)):
   for j in range(len(b)):
     if(a[i]==b[j]):
       b.remove(b[j])  //error here

 print(b)

what is error if i am wring print() statement work fine but b.remove() is not working