Function that uses batch_writer to efficiently(-ish) delete all of the entries in a DynamoDB table

dynamo_truncate_table.py

import boto3
dynamo = boto3.resource('dynamodb')

def truncate_table(table_name):
    table = dynamo.Table(table_name)

    table_key_names = [key.get("AttributeName") for key in table.key_schema]
    response = table.scan(ProjectionExpression=", ".join(table_key_names)
    data = response.get('Items')
    while 'LastEvaluatedKey' in response:
        response = table.scan(ProjectionExpression=ProjectionExpression, ExclusiveStartKey=response['LastEvaluatedKey'])
        data.extend(response['Items'])

    with table.batch_writer() as batch:
        for each in data:
            result = batch.delete_item(
                Key={key: each[key] for key in table_key_names}
            )