

def _process(self, view, key=None):
    retval = self.p.op(view, key)
    if (self.p.output_type is not None):
        assert isinstance(retval, self.p.output_type), 'Return value does not match the declared output type.'
    return retval.relabel(group=self.p.group)

dataset/ETHPy150Open ioam/holoviews/holoviews/operation/element.py operation._process/original