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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_str(cls: Type[CRCPubkeyType], crc_pubkey: str) -> CRCPubkeyType: """ Return CRCPubkey instance from CRC public key string :param crc_pubkey: CRC public key :return: """

        data = CRCPubkey.re_crc_pubkey.match(crc_pubkey)
        if data is None:
            raise Exception("Could not parse CRC public key {0}".format(crc_pubkey))
        pubkey = data.group(1)
        crc = data.group(2)
        return cls(pubkey, crc)