docs: def get_facets(self):
          """ Get facets from the response.
  
              Returns:
                  A dict where requested facet paths are keys and a list of coresponding terms are values.
          """
          return dict([(facet.attrib['path'], [term.text
                                               for term in facet.findall('term')])
                       for facet in self._content.findall('facet')])