code: def addVars(filename, varNamesStr, outOf=None):
      r
      filename, varnames, outOf = __saveVarsHelper(filename, varNamesStr, outOf)
      f = None
      try:
          f = open(filename, "rb")
          h = cPickle.load(f)
          f.close()
  
          h.update(dict(zip(varnames, atIndices(outOf, varnames))))
          f = open(filename, "wb")
          cPickle.dump( h, f , 1 )
      finally:
          if f: f.close()
docs: r"""Like `saveVars`, but appends additional variables to file.