ElementTree-like Python bindings for libxml2 and libxslt

lxml provides a Python 3 binding to the libxslt and libxml2 libraries. It follows the ElementTree API as much as possible in order to provide a more Pythonic interface to libxml2 and libxslt than the default bindings.  In particular, lxml deals with Python Unicode strings rather than encoded UTF-8 and handles memory management automatically, unlike the default bindings.