input: Write a python function to count the occurrence of a target element in a list.
  assert count_element_occurrence([1, 2, 3, 4, 5, 1, 2, 1], 1) == 3
  assert count_element_occurrence([10, 20, 10, 30, 10, 40], 10) == 3
  assert count_element_occurrence([5, 7, 9, 7, 7, 6, 4, 3], 7) == 3
output: def count_element_occurrence(lst, target):
      return lst.count(target)