python生成xml

1. python生成xml，如何把头写成<xml version="1.0">

tree.write('createxml.xml',xml_declaration=True, encoding='utf-8', method="xml")

root = ET.Element('bookstore')
tree = ET.ElementTree()
tree._setroot(root）

child0 = ET.Element('book',{'category':"COOKING"})
root.append(child0)

child00 = ET.Element('title',{'language':"English"})
child00.text='Everyday Italian'
child0.append(child00)

tree.write('createxml.xml','utf-8')