Represent a node in the pipeline. A node can have bunch of input ports and bunch of output ports. Each port has a unique name within the node.
- (property) name: the name of the node, it is unique within a pipeline
- INPUT: a dictionary like object, allowing you to get input port by name, e.g. node.INPUT["foo"] will return the input port with name "foo"
- input: the default input port, e.g. node.input
- OUTPUT: a dictionary like object, allowing you to get output port by name, e.g. node.OUTPUT["foo"] will return the output port with name "foo"
- output: the default input port, e.g. node.output