如何用lxml解析带有表单的结果页?

我尝试用表单解析第二页。我使用以下链接中的示例代码源代码: http://blog.ianbicking.org/2007/09/24/lxmlhtml/ http://www.infofer.ro/ 例如,我使用以下值:

>>> pprint(form.form_values())
[('cboData', '8/30/2010'),
 ('txtPlecare', 'Bucuresti Nord'),
 ('txtSosire', 'Constanta'),
 ('tip', 'GO'),
 ('lng', '1')]

result = parse(submit_form(form)).getroot()

这是另一个表格的另一页。 我试着这样做:

>>> page2=parse(result).getroot()
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/usr/lib/python2.6/site-packages/lxml/html/__init__.py", line 661, in parse
    return etree.parse(filename_or_url, parser, base_url=base_url, **kw)
  File "lxml.etree.pyx", line 2706, in lxml.etree.parse (src/lxml/lxml.etree.c:49945)
  File "parser.pxi", line 1525, in lxml.etree._parseDocument (src/lxml/lxml.etree.c:72026)
TypeError: cannot parse from 'HtmlElement'

如何从第二页解析表单?