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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def __xinclude_lxml(target, source, env):
 """ Resolving XIncludes, using the lxml module. """

    from lxml import etree
    
    doc = etree.parse(str(source[0]))
    doc.xinclude()
    try:
        doc.write(str(target[0]), xml_declaration=True, 
                  encoding="UTF-8", pretty_print=True)
    except:
        pass

    return None