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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 create_jwt(self, expiration=60):
 """ Creates a signed JWT, valid for 60 seconds by default. The expiration can be extended beyond this, to a maximum of 600 seconds. :param expiration: int :return: """

        now = int(time.time())
        payload = {
            "iat": now,
            "exp": now + expiration,
            "iss": self.integration_id
        }
        encrypted = jwt.encode(
            payload,
            key=self.private_key,
            algorithm="RS256"
        )

        if atLeastPython3:
            encrypted = encrypted.decode('utf-8')

        return encrypted