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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_account(self, username, service):
 """Register an account against a service. The account that we're querying must be referenced during any future task requests - so we know which account to link the task too. """

        data = {
            'service': service,
            'username': username,
        }

        return self._perform_post_request(self.register_account_endpoint, data, self.token_header)