code: def dump(obj, fp, *args, **kwargs):
      
      kwargs['default'] = object2dict
  
      json.dump(obj, fp, *args, **kwargs)
docs: Serialize a object to a file object.
  
      Basic Usage:
  
      >>> import simplekit.objson
      >>> from cStringIO import StringIO
      >>> obj = {'name': 'wendy'}
      >>> io = StringIO()
      >>> simplekit.objson.dump(obj, io)
      >>> print io.getvalue()
  
      :param obj: a object which need to dump
      :param fp: a instance of file object
      :param args: Optional arguments that :func:`json.dump` takes.
      :param kwargs: Keys arguments that :func:`json.dump` takes.
      :return: None