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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 generate_access_token( self, name, scope, delegates=None, lifetime=None, retry=google.api_core.gapic_v1.method.DEFAULT, timeout=google.api_core.gapic_v1.method.DEFAULT, metadata=None, ):
 """ Generates an OAuth 2.0 access token for a service account. Example: Args: name (str):
 The resource name of the service account for which the credentials are requested, in the following format: ``projects/-/serviceAccounts/{ACCOUNT_EMAIL_OR_UNIQUEID}``. scope (list[str]):
 Code to identify the scopes to be included in the OAuth 2.0 access token. See https://developers.google.com/identity/protocols/googlescopes for more information. At least one value required. delegates (list[str]):
 The sequence of service accounts in a delegation chain. Each service account must be granted the ``roles/iam.serviceAccountTokenCreator`` role on its next service account in the chain. The last service account in the chain must be granted the ``roles/iam.serviceAccountTokenCreator`` role on the service account that is specified in the ``name`` field of the request. The delegates must have the following format: ``projects/-/serviceAccounts/{ACCOUNT_EMAIL_OR_UNIQUEID}`` lifetime (Union[dict, ~google.cloud.iam_credentials_v1.types.Duration]):
 The desired lifetime duration of the access token in seconds. Must be set to a value less than or equal to 3600 (1 hour). If a value is not specified, the token's lifetime will be set to a default value of one hour. If a dict is provided, it must be of the same form as the protobuf message :class:`~google.cloud.iam_credentials_v1.types.Duration` 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.iam_credentials_v1.types.GenerateAccessTokenResponse` 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 "generate_access_token" not in self._inner_api_calls:
            self._inner_api_calls[
                "generate_access_token"
            ] = google.api_core.gapic_v1.method.wrap_method(
                self.transport.generate_access_token,
                default_retry=self._method_configs["GenerateAccessToken"].retry,
                default_timeout=self._method_configs["GenerateAccessToken"].timeout,
                client_info=self._client_info,
            )

        request = common_pb2.GenerateAccessTokenRequest(
            name=name, scope=scope, delegates=delegates, lifetime=lifetime
        )
        if metadata is None:
            metadata = []
        metadata = list(metadata)
        try:
            routing_header = [("name", 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["generate_access_token"](
            request, retry=retry, timeout=timeout, metadata=metadata
        )