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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_instance( self, update_mask, instance, retry=google.api_core.gapic_v1.method.DEFAULT, timeout=google.api_core.gapic_v1.method.DEFAULT, metadata=None, ):
 """ Updates the metadata and configuration of a specific Redis instance. Completed longrunning.Operation will contain the new instance object in the response field. The returned operation is automatically deleted after a few hours, so there is no need to call DeleteOperation. Example: Args: update_mask (Union[dict, ~google.cloud.redis_v1beta1.types.FieldMask]):
 Required. Mask of fields to update. At least one path must be supplied in this field. The elements of the repeated paths field may only include these fields from ``Instance``: \* ``display_name`` \* ``labels`` \* ``memory_size_gb`` \* ``redis_config`` If a dict is provided, it must be of the same form as the protobuf message :class:`~google.cloud.redis_v1beta1.types.FieldMask` instance (Union[dict, ~google.cloud.redis_v1beta1.types.Instance]):
 Required. Update description. Only fields specified in update\_mask are updated. If a dict is provided, it must be of the same form as the protobuf message :class:`~google.cloud.redis_v1beta1.types.Instance` retry (Optional[google.api_core.retry.Retry]):
 A retry object used to retry requests. If ``None`` is specified, requests will not be retried. timeout (Optional[float]):
 The amount of time, in seconds, to wait for the request to complete. Note that if ``retry`` is specified, the timeout applies to each individual attempt. metadata (Optional[Sequence[Tuple[str, str]]]):
 Additional metadata that is provided to the method. Returns: A :class:`~google.cloud.redis_v1beta1.types._OperationFuture` instance. Raises: google.api_core.exceptions.GoogleAPICallError: If the request failed for any reason. google.api_core.exceptions.RetryError: If the request failed due to a retryable error and retry attempts failed. ValueError: If the parameters are invalid. """

        # Wrap the transport method to add retry and timeout logic.
        if "update_instance" not in self._inner_api_calls:
            self._inner_api_calls[
                "update_instance"
            ] = google.api_core.gapic_v1.method.wrap_method(
                self.transport.update_instance,
                default_retry=self._method_configs["UpdateInstance"].retry,
                default_timeout=self._method_configs["UpdateInstance"].timeout,
                client_info=self._client_info,
            )

        request = cloud_redis_pb2.UpdateInstanceRequest(
            update_mask=update_mask, instance=instance
        )
        operation = self._inner_api_calls["update_instance"](
            request, retry=retry, timeout=timeout, metadata=metadata
        )
        return google.api_core.operation.from_gapic(
            operation,
            self.transport._operations_client,
            cloud_redis_pb2.Instance,
            metadata_type=any_pb2.Any,
        )