input: Write a python function to count the occurrences of each element in a list using the Counter class from the collections module.
  assert count_occurrences([2, 4, 7, 1, 6, 4, 7, 2, 6, 3]) == {2: 2, 4: 2, 7: 2, 1: 1, 6: 2, 3: 1}
  assert count_occurrences([1, 1, 2, 2, 3, 3, 3]) == {1: 2, 2: 2, 3: 3}
  assert count_occurrences([5, 5, 5, 5, 5]) == {5: 5}
output: from collections import Counter
  
  def count_occurrences(lst):
      return dict(Counter(lst))