1. 确认您的VPC已设置站点到站点VPN连接。您可使用以下代码示例来创建VPC及相关资源：

import boto3

ec2 = boto3.resource('ec2')

vpc = ec2.create_vpc(CidrBlock='10.0.0.0/16')
vpc.create_tags(Tags=[{"Key": "Name", "Value": "my_vpc"}])

gateway = ec2.create_internet_gateway()
gateway.attach_to_vpc(VpcId=vpc.id)
gateway.create_tags(Tags=[{"Key": "Name", "Value": "my_gateway"}])

route_table = vpc.create_route_table()
route = route_table.create_route(
    DestinationCidrBlock='0.0.0.0/0',
    GatewayId=gateway.id
)

subnet1 = ec2.create_subnet(CidrBlock='10.0.1.0/24', VpcId=vpc.id)
subnet1.create_tags(Tags=[{"Key": "Name", "Value": "my_subnet_1"}])

subnet2 = ec2.create_subnet(CidrBlock='10.0.2.0/24', VpcId=vpc.id)
subnet2.create_tags(Tags=[{"Key": "Name", "Value": "my_subnet_2"}])

2. 创建一个虚拟专用网关(VPN Gateway)，使用以下代码示例：

import boto3

ec2 = boto3.client('ec2')

response = ec2.create_vpn_gateway(
    Type='ipsec.1',
    AmazonSideAsn=64512
)

3. 创建一个VPN连接(VPN Connection)，使用以下代码示例：

import boto3

ec2 = boto3.client('ec2')

response = ec2.create_vpn_connection(
    CustomerGatewayId='cgw-1234567890abcdef',
    Type='ipsec.1',
    VpnGatewayId='vgw-1234567890abcdef',
    Options={
        'StaticRoutesOnly': False
    },
    TagSpecifications=[
        {
            'ResourceType': 'vpn-connection',
            'Tags': [
                {
                    'Key': 'Name',
                    'Value': 'my_vpn_connection'
                },
            ]
        },
    ]
)

4. 配置VPN连接(VPN connection)，并定义子网到VPC路由。参照以下Python代码示例：

import boto3

ec2 = boto3.resource('ec2')

# Import the names of your subnets
subnet_name_1 = "my_subnet_1"
subnet_name_2 = "my_subnet_2