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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 verify1(self):
 """First device verification step."""

        self._check_initialized()
        self._verify_private = curve25519.Private(secret=self.seed)
        self._verify_public = self._verify_private.get_public()
        log_binary(_LOGGER,
                   'Verification keys',
                   Private=self._verify_private.serialize(),
                   Public=self._verify_public.serialize())
        verify_public = self._verify_public.serialize()
        return b'\x01\x00\x00\x00' + verify_public + self._auth_public