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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 update(self):
 """ Updates the information the Pump server has about the client """

        error = ""

        if self.key is None:
            error = "To update a client you need to provide a key"
        if self.secret is None:
            error = "To update a client you need to provide the secret"

        if error:
            raise ClientException(error)

        self.request()
        return True