def __init__(self, *args, **kwargs):
self.anchor = None <EOL>self.chunks = []   <EOL>Chunk.__init__(self, *args, **kwargs)<EOL>
A chunk of chunks that make up a prepositional noun phrase (i.e., PP + NP).
            When the output of the parser includes PP-attachment,
            PNPChunck.anchor will yield the chunk that is clarified by the preposition.
            For example: "the cat went [for the mouse] [with its claws]":
            - [went] what? => for the mouse,
            - [went] how? => with its claws.