input: Write a function to optimize a given Python program that prints each element of a list on a new line. If the input list is empty, the function should return an empty string. The function should handle lists of any length, including very large lists.
  assert optimize_print_list([1, 2, 3, 4, 5, 6])=='''1
  2
  3
  4
  5
  6'''
  assert optimize_print_list([])==''
  assert optimize_print_list([10, 20, 30])=='''10
  20
  30'''
  assert optimize_print_list([1, 2, 3, 4, 5, 6, 7, 8, 9, 10])=='''1
  2
  3
  4
  5
  6
  7
  8
  9
  10'''
  assert optimize_print_list([1])=='''1'''
output: def optimize_print_list(lst):
      if not lst:
          return ''
      return '\n'.join(map(str, lst))