code: def _handle_struct(toks):
          
          subtrees = toks[1:-1]
          signature = ''.join(s for (_, s) in subtrees)
          funcs = [f for (f, _) in subtrees]
  
          def the_func(a_list, variant=0):
              """
              Function for generating a Struct from a list.
  
              :param a_list: the list to transform
              :type a_list: list or tuple
              :param int variant: variant index
              :returns: a dbus Struct of transformed values and variant level
              :rtype: Struct * int
              :raises IntoDPValueError:
              """
              if isinstance(a_list, dict):
                  raise IntoDPValueError(a_list, "a_list",
                                         "must be a simple sequence, is a dict")
              if len(a_list) != len(funcs):
                  raise IntoDPValueError(
                      a_list,
                      "a_list",
                      "must have exactly %u items, has %u" % \
                        (len(funcs), len(a_list))
                  )
              elements = [f(x) for (f, x) in zip(funcs, a_list)]
              level = 0 if elements == [] else max(x for (_, x) in elements)
              (obj_level, func_level) = \
                  _ToDbusXformer._variant_levels(level, variant)
              return (dbus.types.Struct(
                  (x for (x, _) in elements),
                  signature=signature,
                  variant_level=obj_level), func_level)
  
          return (the_func, '(' + signature + ')')
docs: Generate the correct function for a struct signature.
  
          :param toks: the list of parsed tokens
          :returns: function that returns an Array or Dictionary value
          :rtype: ((list or tuple) -> (Struct * int)) * str