code: def fetch(*args, **kwargs):
      
      data = kwargs.get('data', None)
      files = kwargs.get('files', {})
  
      if data and isinstance(data, (basestring, dict)) or files:
          return post(*args, **kwargs)
      return get(*args, **kwargs)
docs: fetch an URL.
  
      :func:`~urlfetch.fetch` is a wrapper of :func:`~urlfetch.request`.
      It calls :func:`~urlfetch.get` by default. If one of parameter ``data``
      or parameter ``files`` is supplied, :func:`~urlfetch.post` is called.