input: Write a python function to find the starting indices of all occurrences of a subsequence in a list.
  assert find_sequence([1, 2, 3, 1, 2, 3, 1, 2], [1, 2]) == [0, 3, 6]
  assert find_sequence([1, 2, 3, 4, 5, 6], [4, 5, 6]) == [3]
  assert find_sequence([1, 2, 3, 4, 2, 3], [2, 3]) == [1, 4]
output: def find_sequence(lst, subseq):
      indices = []
      len_subseq = len(subseq)
      for i in range(len(lst) - len_subseq + 1):
          if lst[i:i + len_subseq] == subseq:
              indices.append(i)
      return indices