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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 from_cid(cls, cid, **kwargs):
 """Retrieve the Compound record for the specified CID. Usage:: c = Compound.from_cid(6819) :param int cid: The PubChem Compound Identifier (CID). """

        record = json.loads(request(cid, **kwargs).read().decode())['PC_Compounds'][0]
        return cls(record)