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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 export_agent(self, parent, agent_uri=None, retry=google.api_core.gapic_v1.method.DEFAULT, timeout=google.api_core.gapic_v1.method.DEFAULT, metadata=None):
 """ Exports the specified agent to a ZIP file. Operation <response: ``ExportAgentResponse``, metadata: [google.protobuf.Struct][google.protobuf.Struct]> Example: Args: parent (str):
 Required. The project that the agent to export is associated with. Format: ``projects/<Project ID>``. agent_uri (str):
 Optional. The Google Cloud Storage URI to export the agent to. Note: The URI must start with \"gs://\". If left unspecified, the serialized agent is returned inline. 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.dialogflow_v2.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 'export_agent' not in self._inner_api_calls:
            self._inner_api_calls[
                'export_agent'] = google.api_core.gapic_v1.method.wrap_method(
                    self.transport.export_agent,
                    default_retry=self._method_configs['ExportAgent'].retry,
                    default_timeout=self._method_configs['ExportAgent']
                    .timeout,
                    client_info=self._client_info,
                )

        request = agent_pb2.ExportAgentRequest(
            parent=parent,
            agent_uri=agent_uri,
        )
        operation = self._inner_api_calls['export_agent'](
            request, retry=retry, timeout=timeout, metadata=metadata)
        return google.api_core.operation.from_gapic(
            operation,
            self.transport._operations_client,
            agent_pb2.ExportAgentResponse,
            metadata_type=struct_pb2.Struct,
        )