>>> import copy
>>> from xml.dom import minidom

>>> doc = minidom.parseString('<root/>')
>>> doc2 = copy.deepcopy(doc)

>>> doc.toxml()
u'<?xml version="1.0" ?><root/>'
>>> doc2.toxml()
u'<?xml version="1.0" ?><root/><root/>'
>>> minidom.parseString(doc2.toxml())
Traceback (most recent call last):
...
ExpatError: junk after document element: line 1, column 2


The workaround is to use doc.cloneNode(True).