input: Write a python function to find the index of a target value in a list.
  assert find_index([1, 2, 3, 4, 5], 3) == 2
  assert find_index([10, 20, 30, 40, 50], 50) == 4
  assert find_index([5, 10, 15, 20, 25], 100) == -1
output: def find_index(lst, target):
      try:
          return lst.index(target)
      except ValueError:
          return -1