anchor.diff:  
   sort_index(Pid, DataFrame, _Axis, Keywords) ->
       gen_server:call(Pid, {'core.jun.dataframe', [DataFrame, sort_index, [], 'None', Keywords]}, infinity).
  +
  +%% Legacy
  +
  +legacy_query(Pid, DataFrame, Query, _Keywords) ->
  +    [Column, Operator, Value] = jun_parser:query(Query),
  +    gen_server:call(Pid, {'core.jun', legacy_query, [DataFrame, Column, Operator, Value]}, infinity).
  +
  +legacy_assignment(Pid, DataFrame, Value, Keywords) ->
  +    % from keywords get the column to assign
  +    Column = begin
  +        ColumnAtom = proplists:get_value(column, Keywords, <<>>),
  +        ColumnList = atom_to_list(ColumnAtom),
  +        list_to_binary(ColumnList)
  +    end,
  +    gen_server:call(Pid, {'core.jun', legacy_assignment, [DataFrame, Column, Value]}, infinity).
  
positive.code: 
  -export(['query'/4,
      head/4,
      tail/4,
      legacy_query/4]).
  
  -export([to_erl/2]).
  
  
negative.code: 
  tail(Pid, DataFrame, N, Keywords) ->
      gen_server:call(Pid, {'core.jun.dataframe', [DataFrame, tail, [N], 'None', Keywords]}, infinity).
  
  %% Helpers
  
  