求交集小练手

def diff_of_element_list(lst, k):
    newlst = [i + k for i in lst]
    print(set(newlst))
    print(set(lst))
    return set(lst) & set(newlst)#求交集，&求交集

if __name__ == '__main__':
    lst = [7, 6, 23, 19, 10, 11, 9, 3, 15]
    k = 4
    print(diff_of_element_list(lst, k))