1. 首先，获取AWS Config的查询结果。

import boto3

client = boto3.client('config')

query = "SELECT accountId, resourceType \
         WHERE resourceType = 'AWS::EC2::Instance'"

response = client.select_resource_config(Expression=query)

2. 然后，使用Python的collections模块中的defaultdict方法按group by的字段进行分组。

from collections import defaultdict

group_by_field = 'accountId' # group by字段，可以根据需要更改

grouped_data = defaultdict(list)
for item in response['Results']:
    grouped_data[item[group_by_field]].append(item)

3. 最后，对分组后的数据进行处理或打印。

for group_name, group_data in grouped_data.items():
    ## do something with group_data, such as printing or processing
    print(f"Group Name: {group_name}")
    for item in group_data:
        print(f"\t{item['resourceType']} - {item['resourceId']}")