text: """Fixer that cleans up a tuple argument to isinstance after the tokens
  in it were fixed.  This is mainly used to remove double occurrences of
  tokens as a leftover of the long -> int / unicode -> str conversion.
  
  eg.  isinstance(x, (int, long)) -> isinstance(x, (int, int))
         -> isinstance(x, int)
  """
  from .. import fixer_base
  from ..fixer_util import token
  
  
  class FixIsinstance(fixer_base.BaseFix):
      BM_compatible = True
      PATTERN = """
      power<
          'isinstance'
          trailer< '(' arglist< any ',' atom< '('
              args=testlist_gexp< any+ >
          ')' > > ')' >
      >
      """
      run_order = 6
  
      def transform(self, node, results):
          names_inserted = set()
          testlist = results['args']
          args = testlist.children
          new_args = []
          iterator = enumerate(args)
          for idx, arg in iterator:
              if arg.type == token.NAME and arg.value in names_inserted:
                  if idx < len(args) - 1 and args[idx + 1].type == token.COMMA:
                      next(iterator)
                      continue
              else:
                  new_args.append(arg)
                  if arg.type == token.NAME:
                      names_inserted.add(arg.value)
          if new_args and new_args[-1].type == token.COMMA:
              del new_args[-1]
          if len(new_args) == 1:
              atom = testlist.parent
              new_args[0].prefix = atom.prefix
              atom.replace(new_args[0])
          else:
              args[:] = new_args
              node.changed()
  