@property
    def input(self):

        if len(self.inputs) == 1:
            return self.inputs[0]
        else:
            raise Exception("Single input requested. Node has none or more than one input (%d)."
                                    % len(self.inputs))
Return single node imput if exists. Convenience property for nodes which process only one
dataset/ETHPy150Open Stiivi/brewery/brewery/nodes/base.py/Node.input