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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 step1(self, pin):
 """First pairing step."""

        context = SRPContext(
            'Pair-Setup', str(pin),
            prime=constants.PRIME_3072,
            generator=constants.PRIME_3072_GEN,
            hash_func=hashlib.sha512)
        self._session = SRPClientSession(
            context, binascii.hexlify(self._auth_private).decode())