input: Write a function that takes a list and a search query as input and returns the indices of all elements in the list which match the search query. If the search query is not found in the list, the function should return an empty list. If the input list is empty, it should return an empty list as well.
  assert search_list(["apple", "banana", "peach", "orange", "grape"], "apple")==[0]
  assert search_list(["apple", "banana", "peach", "orange", "grape"], "grape")==[4]
  assert search_list(["apple", "banana", "peach", "orange", "grape"], "mango")==[]
  assert search_list(["red", "blue", "red", "green"], "red")==[0, 2]
  assert search_list([], "apple")==[]
output: def search_list(lst, query):
      return [i for i, item in enumerate(lst) if item == query]