AWS Lambda Function无法插入Dynamo DB

Question

我有一个简单的AWS Lambda函数（节点）。我要做的就是将数据插入DynamoDB数据库，但不会。我已经验证了该数据库的名称为col。没有错误，我正在遵循的教程完全可以满足我的需求……我在做什么错了？

const TABLE = "pets"
const AWS = require('aws-sdk');
const dynamo = new AWS.DynamoDB({
    apiVersion: '2012-08-10'
});

exports.handler = async (event, context, callback) => {

    const done = function(err, data) {
        var statusCode = '20';
        var body = 'SUCCESS';

        console.log("[" + data + "]");

        if (err) {
            statusCode = '500';
            body = err
        }

        callback(null, {
            statusCode: statusCode,
            body: {
                m: body,
                method: event.httpMethod
            }
        });
    }

    switch (event.httpMethod) {
        case "POST":
            var a = dynamo.putItem({
                TableName: TABLE,
                Item: {
                    name: {
                        S: "cat"
                    }
                }
            }, done);

            break; 
        case "GET":
        default:
    }
};