docs: def append_index(self, name, value=None, sublist=None, seq=None):
          """Add one name/value entry to the main context of the rolne and
          return the index number for the new entry.
  
          If you are wanting to "append" another rolne, see the 'extend'
          method instead.
  
          Example of use:
  
          >>> # setup an example rolne first
          >>> my_var = rolne()
          >>> index = my_var.append_index("item", "zing")
          >>> print index
          0
          >>> my_var["item", "zing", index].append("size", "4")
          >>> my_var["item", "zing", index].append("color", "red")
          >>> print my_var
          %rolne:
          item = zing
              size = 4
              color = red
          <BLANKLINE>
          >>> index = my_var.append_index("item", "zing")
          >>> print index
          1
          >>> my_var["item", "zing", index].append("size", "2")
          >>> my_var["item", "zing", index].append("color", "blue")
          >>> print my_var
          %rolne:
          item = zing
              size = 4
              color = red
          item = zing
              size = 2
              color = blue
          <BLANKLINE>
  
          .. versionadded:: 0.1.4
          
          :param name:
             The key name of the name/value pair.
          :param value:
             The key value of the name/value pair. If not passed, then the value
             is assumed to be None.
          :param sublist:
             An optional parameter that also appends a subtending list of entries.
             It is not recommended that this parameter be used.
          :returns:
             An integer representing the index of the newly inserted name/pair.
          """
          if sublist is None:
              sublist = []
          new_tuple = (name, value, sublist, lib._seq(self, seq))
          self.data.append(new_tuple)
          index = len(self.list_values(name, value)) - 1
          return index