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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 should_check_ciphersuites(self):
 """ We extract cipher suites candidates from the client's proposition. """

        if isinstance(self.mykey, PrivKeyRSA):
            kx = "RSA"
        elif isinstance(self.mykey, PrivKeyECDSA):
            kx = "ECDSA"
        if get_usable_ciphersuites(self.cur_pkt.ciphers, kx):
            return
        raise self.NO_USABLE_CIPHERSUITE()