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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 list_events( self, project_name, group_id, service_filter=None, time_range=None, page_size=None, retry=google.api_core.gapic_v1.method.DEFAULT, timeout=google.api_core.gapic_v1.method.DEFAULT, metadata=None, ):
 """ Lists the specified events. Example: Args: project_name (str):
 [Required] The resource name of the Google Cloud Platform project. Written as ``projects/`` plus the `Google Cloud Platform project ID <https://support.google.com/cloud/answer/6158840>`__. Example: ``projects/my-project-123``. group_id (str):
 [Required] The group for which events shall be returned. service_filter (Union[dict, ~google.cloud.errorreporting_v1beta1.types.ServiceContextFilter]):
 [Optional] List only ErrorGroups which belong to a service context that matches the filter. Data for all service contexts is returned if this field is not specified. If a dict is provided, it must be of the same form as the protobuf message :class:`~google.cloud.errorreporting_v1beta1.types.ServiceContextFilter` time_range (Union[dict, ~google.cloud.errorreporting_v1beta1.types.QueryTimeRange]):
 [Optional] List only data for the given time range. If not set a default time range is used. The field time\_range\_begin in the response will specify the beginning of this time range. If a dict is provided, it must be of the same form as the protobuf message :class:`~google.cloud.errorreporting_v1beta1.types.QueryTimeRange` page_size (int):
 The maximum number of resources contained in the underlying API response. If page streaming is performed per- resource, this parameter does not affect the return value. If page streaming is performed per-page, this determines the maximum number of resources in a page. 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.gax.PageIterator` instance. By default, this is an iterable of :class:`~google.cloud.errorreporting_v1beta1.types.ErrorEvent` instances. This object can also be configured to iterate over the pages of the response through the `options` parameter. 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 "list_events" not in self._inner_api_calls:
            self._inner_api_calls[
                "list_events"
            ] = google.api_core.gapic_v1.method.wrap_method(
                self.transport.list_events,
                default_retry=self._method_configs["ListEvents"].retry,
                default_timeout=self._method_configs["ListEvents"].timeout,
                client_info=self._client_info,
            )

        request = error_stats_service_pb2.ListEventsRequest(
            project_name=project_name,
            group_id=group_id,
            service_filter=service_filter,
            time_range=time_range,
            page_size=page_size,
        )
        if metadata is None:
            metadata = []
        metadata = list(metadata)
        try:
            routing_header = [("project_name", project_name)]
        except AttributeError:
            pass
        else:
            routing_metadata = google.api_core.gapic_v1.routing_header.to_grpc_metadata(
                routing_header
            )
            metadata.append(routing_metadata)

        iterator = google.api_core.page_iterator.GRPCIterator(
            client=None,
            method=functools.partial(
                self._inner_api_calls["list_events"],
                retry=retry,
                timeout=timeout,
                metadata=metadata,
            ),
            request=request,
            items_field="error_events",
            request_token_field="page_token",
            response_token_field="next_page_token",
        )
        return iterator