title: How to group tokens placed in different positions using pyparsing?
body: <p>I have a simple sentence - "<em>tok0,084040,tok1,tok2,231108</em>" where <strong>084040</strong> is time (08:40:40) and <strong>231108</strong> is date (23.11.2008)</p>
  
  <p>Following the pyparsing documentation I've written the rules to parse the tokens:
  <code><pre>
      from pyparsing import *
      d = Literal(',').suppress()
      two_digits = Word(nums, exact=2)
      tok0 = Word(nums)
      time_token = two_digits("hour") + two_digits("min") + two_digits("sec")
      tok1 = Word(alphas)
      tok2 = oneOf('A B C')
      date_token = two_digits("day") + two_digits("month") + two_digits("year")
      grammar = (tok0 + d + time_token + d + tok1 + d + tok2 + d + date_token)
  </pre></code>
  What I want is to have a logical group in my <strong>ParseResults</strong> consisting of <strong>time_token</strong> and <strong>date_token</strong> so that I could use <strong>setParseAction</strong>, <strong>setResultsName</strong> for the group. Something like <code><pre>Group(time_token + date_token)</pre></code> considering they are not adjacent. 
  <code><pre>dreamGroup = Group(time_token + date_token)("datetime").setParseAction(myFn)
  parseResults = grammar.parseString("123,084040,ABC,A,231108")
  datetime = parseResults.datetime</pre></code>
  P.S.: The result of the grammar.parseString should be an instance of ParseResults.</p>