input: Write a python function to search for all occurrences of a query in a list and return their indices.
  assert search_list([1, 2, 3, 2, 4, 2], 2) == [1, 3, 5]
  assert search_list(['apple', 'banana', 'cherry', 'banana'], 'banana') == [1, 3]
  assert search_list([5, 10, 15, 20], 25) == []
  assert search_list([], 1) == []
output: def search_list(lst, query):
      return [i for i, x in enumerate(lst) if x == query]