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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 register(self, server=None):
 """ Registers the client with the Pump API retrieving the id and secret """

        if (self.key or self.secret):
            return self.update()

        server_data = self.request(server)

        self.key = server_data["client_id"]
        self.secret = server_data["client_secret"]
        self.expirey = server_data["expires_at"]