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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 get_log_metric( self, metric_name, retry=google.api_core.gapic_v1.method.DEFAULT, timeout=google.api_core.gapic_v1.method.DEFAULT, metadata=None, ):
 """ Gets a logs-based metric. Example: Args: metric_name (str):
 The resource name of the desired metric: :: "projects/[PROJECT_ID]/metrics/[METRIC_ID]" 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.logging_v2.types.LogMetric` 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 "get_log_metric" not in self._inner_api_calls:
            self._inner_api_calls[
                "get_log_metric"
            ] = google.api_core.gapic_v1.method.wrap_method(
                self.transport.get_log_metric,
                default_retry=self._method_configs["GetLogMetric"].retry,
                default_timeout=self._method_configs["GetLogMetric"].timeout,
                client_info=self._client_info,
            )

        request = logging_metrics_pb2.GetLogMetricRequest(metric_name=metric_name)
        if metadata is None:
            metadata = []
        metadata = list(metadata)
        try:
            routing_header = [("metric_name", metric_name)]
        except AttributeError:
            pass
        else:
            routing_metadata = google.api_core.gapic_v1.routing_header.to_grpc_metadata(
                routing_header
            )
            metadata.append(routing_metadata)

        return self._inner_api_calls["get_log_metric"](
            request, retry=retry, timeout=timeout, metadata=metadata
        )