Python XSLT Transformation

XSLTransform.py

from StringIO import StringIO
from lxml import etree

xslt_root = etree.XML('''\
<xsl:stylesheet version="1.0"
  xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
  <xsl:template match="/">
    <foo><xsl:value-of select="/a/b/text()" /></foo>
  </xsl:template>
</xsl:stylesheet>''')
transform = etree.XSLT(xslt_root)

f = StringIO('<a><b>Hello World!</b></a>')
doc = etree.parse(f)
result_tree = transform(doc)

root = etree.XML('<a><b>Text</b></a>')
result = transform(root)
xml = str(result)