input: from typing import List
  
  def construct_xml(items: List[str]) -> None:
      """Construct an XML document using Python which contains the given list of items.
      >>> construct_xml(['Item1', 'Item2', 'Item3'])
      Output is saved in 'data.xml' containing XML structure with elements 'item' for each item in the list.
      """
output:     with open('data.xml', 'w') as file:
          file.write('<root>\n')
          for item in items:
              file.write(f'    <item>{item}</item>\n')
          file.write('</root>\n')