Python-сообщество

<root>
    <item1>text</item1>
    <item2 attr1="attr1"/>
</root>

<root>
    <item1text</item1>
    em2 attr1="attr1"/>
</root>

<root>
    <item1>text</item1>
    <item2 attr1="attr1"/>
</root>

<root>
    <item1text</item1>
    em2 attr1="attr1"/>
</root>

#-*- codepage: cp1251 -*-

from xml.etree.ElementTree import ElementTree

def verifyXml(filename):
  tree = ElementTree()
  try:
    tree.parse(filename)
  except:
    return False

  return True

def main():
  for f in ['valid.xml', 'invalid.xml']:
    print 'File %s is %s' % (f, 'valid' if verifyXml(f) else 'invalid')

if __name__ == '__main__':
  main()

File valid.xml is valid
File invalid.xml is invalid