input: Write a python function to find the mode (the number that appears most frequently) in a list.
  assert get_mode([1, 1, 2, 2, 2]) == 2
  assert get_mode([1, 2, 3, 3, 4, 4, 4, 5, 5, 5, 5]) == 5
  assert get_mode([7, 7, 7, 3, 3, 2, 2, 2, 2, 5, 5, 5]) == 2
output: def get_mode(lst):
      from collections import Counter
      count = Counter(lst)
      return max(count, key=count.get)