You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: spanner_alter_sequence.go
    path of file: ./repos/golang-samples/spanner/spanner_snippets/spanner
    
    the code of the file until where you have to start completion: // Copyright 2023 Google LLC
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

package spanner

// [START spanner_alter_sequence]

import (
	"context"
	"fmt"
	"io"

	"cloud.google.com/go/spanner"
	database "cloud.google.com/go/spanner/admin/database/apiv1"
	adminpb "cloud.google.com/go/spanner/admin/database/apiv1/databasepb"
	"google.golang.org/api/iterator"
)

func alterSequence(w io.Writer, db string) error {
	// db := "projects/my-project/instances/my-instance/databases/my-database"
	ctx := context.Background()
	adminClient, err := database.NewDatabaseAdminClient(ctx)
	if err != nil {
		return err
	}
	defer adminClient.Close()

	// List of DDL statements to be applied to the database.
	// Alter the sequence to skip range [1000-5000000] for new keys.
	ddl := []string{
		"ALTER SEQUENCE Seq SET OPTIONS (skip_range_min = 1000, skip_range_max = 5000000)",
	}
	op, err := adminClient.UpdateDatabaseDdl(ctx, &adminpb.UpdateDatabaseDdlRequest{
		Database:   db,
		Statements: ddl,
	})
	if er
    
func alterSequence(w io.Writer, db string) error {
	// db := "projects/my-project/instances/my-instance/databases/my-database"
	ctx := context.Background()
	adminClient, err := database.NewDatabaseAdminClient(ctx)
	if err != nil {
		return err
	}
	defer adminClient.Close()

	// List of DDL statements to be applied to the database.
	// Alter the sequence to skip range [1000-5000000] for new keys.
	ddl := []string{
		"ALTER SEQUENCE Seq SET OPTIONS (skip_range_min = 1000, skip_range_max = 5000000)",
	}
	op, err := adminClient.UpdateDatabaseDdl(ctx, &adminpb.UpdateDatabaseDdlRequest{
		Database:   db,
		Statements: ddl,
	})
	if err != nil {
		return err
	}
	// Wait for the UpdateDatabaseDdl operation to finish.
	if err := op.Wait(ctx); err != nil {
		return fmt.Errorf("waiting for bit reverse sequence skip range to finish failed: %w", err)
	}
	fmt.Fprintf(w, "Altered Seq sequence to skip an inclusive range between 1000 and 5000000\n")

	client, err := spanner.NewClient(ctx, db)
	if err != nil {
		return err
	}
	defer client.Close()

	// Inserts records into the Customers table.
	// The ReadWriteTransaction function returns the commit timestamp and an error.
	// The commit timestamp is ignored in this case.
	_, err = client.ReadWriteTransaction(ctx, func(ctx context.Context, txn *spanner.ReadWriteTransaction) error {
		stmt := spanner.Statement{
			SQL: `INSERT INTO Customers (CustomerName) VALUES ('Lea'), ('Catalina'), ('Smith') THEN RETURN CustomerId`,
		}
		iter := txn.Query(ctx, stmt)
		defer iter.Stop()
		for {
			row, err := iter.Next()
			if err == iterator.Done {
				break
			}
			if err != nil {
				return err
			}
			var customerId int64
			if err := row.Columns(&customerId); err != nil {
				return err
			}
			fmt.Fprintf(w, "Inserted customer record with CustomerId: %d\n", customerId)
		}
		fmt.Fprintf(w, "Number of customer records inserted is: %d\n", iter.RowCount)
		return nil
	})
	return err
}