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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def dump(pif, fp, **kwargs):
 """ Convert a single Physical Information Object, or a list of such objects, into a JSON-encoded text file. :param pif: Object or list of objects to serialize. :param fp: File-like object supporting .write() method to write the serialized object(s) to. :param kwargs: Any options available to json.dump(). """

    return json.dump(pif, fp, cls=PifEncoder, **kwargs)