def METHOD_NAME():
    ec2 = boto3.client("ec2", region_name="us-west-1")
    gateway_id1 = ec2.create_transit_gateway(Description="my first gateway")[
        "TransitGateway"
    ]["TransitGatewayId"]
    gateway_id2 = ec2.create_transit_gateway(Description="my second gateway")[
        "TransitGateway"
    ]["TransitGatewayId"]
    response = ec2.create_transit_gateway_peering_attachment(
        TransitGatewayId=gateway_id1,
        PeerTransitGatewayId=gateway_id2,
        PeerAccountId=ACCOUNT_ID,
        PeerRegion="us-east-1",
    )
    assert "TransitGatewayPeeringAttachment" in response
    attachment = response["TransitGatewayPeeringAttachment"]
    assert attachment["TransitGatewayAttachmentId"].startswith("tgw-attach-")
    assert attachment["RequesterTgwInfo"]["TransitGatewayId"] == gateway_id1
    assert attachment["AccepterTgwInfo"]["TransitGatewayId"] == gateway_id2
    all_attachments = ec2.describe_transit_gateway_peering_attachments()[
        "TransitGatewayPeeringAttachments"
    ]
    our_attachment = [
        att
        for att in all_attachments
        if att["TransitGatewayAttachmentId"] == attachment["TransitGatewayAttachmentId"]
    ]
    assert our_attachment == [attachment]