class_docstr: HTML to DataFrame parser that uses lxml under the hood.
  
  Warning
  -------
  This parser can only handle HTTP, FTP, and FILE urls.
  
  See Also
  --------
  _HtmlFrameParser
  _BeautifulSoupLxmlFrameParser
  
  Notes
  -----
  Documentation strings for this class are in the base class
  :class:`_HtmlFrameParser`.
class_docstr_tok: ["HTML","to","DataFrame","parser","that","uses","lxml","under","the","hood",".","Warning","--","--","--","-","This","parser","can","only","handle","HTTP",",","FTP",",","and","FILE","urls",".","See","Also","--","--","--","--","_HtmlFrameParser","_BeautifulSoupLxmlFrameParser","Notes","--","--","-","Documentation","strings","for","this","class","are","in","the","base","class",":","class",":","`","_HtmlFrameParser","`","."]
code: def _parse_thead_tr(self, table):
      rows = []
  
      for thead in table.xpath(".//thead"):
          rows.extend(thead.xpath("./tr"))
  
          # HACK: lxml does not clean up the clearly-erroneous
          # <thead><th>foo</th><th>bar</th></thead>. (Missing <tr>). Add
          # the <thead> and _pretend_ it's a <tr>; _parse_td() will find its
          # children as though it's a <tr>.
          #
          # Better solution would be to use html5lib.
          elements_at_root = thead.xpath("./td|./th")
          if elements_at_root:
              rows.append(thead)
  
      return rows
  
imports: from distutils.version import LooseVersion
  import numbers
  import os
  import re
  import pandas.compat
  from pandas.compat import binary_type, iteritems, lmap, lrange, raise_with_traceback, string_types, u
  from pandas.errors import AbstractMethodError, EmptyDataError
  from pandas.core.dtypes.common import is_list_like
  from pandas import Series
  from pandas.io.common import _is_url, _validate_header_arg, urlopen
  from pandas.io.formats.printing import pprint_thing
  from pandas.io.parsers import TextParser
label_desc: Use image node_id 7 for calling the _LxmlFrameParser obj's underlying member method code with example usage: obj._parse_thead_tr(table) and returns: rows