# Write a Python program to find common elements in three lists using sets # Python3 program to find common elements # in three lists using sets  def IntersecOfSets(arr1, arr2, arr3):    # Converting the arrays into sets    s1 = set(arr1)    s2 = set(arr2)    s3 = set(arr3)          # Calculates intersection of     # sets on s1 and s2    set1 = s1.intersection(s2)         #[80, 20, 100]          # Calculates intersection of sets    # on set1 and s3    result_set = set1.intersection(s3)          # Converts resulting set to list    final_list = list(result_set)    print(final_list)  # Driver Codeif __name__ == '__main__' :          # Elements in Array1    arr1 = [1, 5, 10, 20, 40, 80, 100]          # Elements in Array2    arr2 = [6, 7, 20, 80, 100]          # Elements in Array3    arr3 = [3, 4, 15, 20, 30, 70, 80, 120]          # Calling Function    IntersecOfSets(arr1, arr2, arr3)