input: Write a function to find the most frequent item in a list.
  assert most_frequent_item([1, 2, 3, 2, 4, 2]) == 2
  assert most_frequent_item([5, 5, 5, 1, 1, 2]) == 5
  assert most_frequent_item([3, 3, 3, 2, 2, 1, 1, 1, 1]) == 1
output: def most_frequent_item(lst):
      from collections import Counter
      return Counter(lst).most_common(1)[0][0]