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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 jsonHook(encoded):
 """Custom JSON decoder that allows construction of a new ``Ci`` instance from a decoded JSON object. :param encoded: a JSON decoded object literal (a dict) :returns: "encoded" or one of the these objects: :class:`Ci`, :class:`MzmlProduct`, :class:`MzmlPrecursor` """

        if '__Ci__' in encoded:
            return Ci._fromJSON(encoded['__Ci__'])
        elif '__MzmlProduct__' in encoded:
            return MzmlProduct._fromJSON(encoded['__MzmlProduct__'])
        elif '__MzmlPrecursor__' in encoded:
            return MzmlPrecursor._fromJSON(encoded['__MzmlPrecursor__'])
        else:
            return encoded