def updata_ddbone(age):
    client = boto3.client('dynamodb')
    response = client.update_item(
            TableName='abc',
            Key={
                'name': {
                    'S': "name"
                }
            },
            AttributeUpdates={
                'age': {
                    'Value': {
                        'S': age
                    }}})

def updata_ddb(name,msg,alias):
    table = boto3.client('dynamodb')
    table.update_item(TableName='hehe',
        Key={'name': {'S':name}},
        UpdateExpression='SET name = :name, alias = :alias',
        ExpressionAttributeValues={
        ':name': {
            'S': msg},
        ':alias':{
            'S': alias}
            })

def get_item(itemkey):
    client = boto3.client('dynamodb',
                          region_name='cn-northwest-1',
                          aws_access_key_id=ak,
                          aws_secret_access_key=sk,
                          aws_session_token=None)
    res = client.get_item(TableName='hehe',Key={'name':{'S':itemkey}})
    name = res['Item']['name']['S']
    print(name)

if __name__ == '__main':
    get_item("name")

def put_ddb(name,alias):
    ddb= boto3.client('dynamodb')
    tableName = 'hehe'
    item = {  'mykey': {'S': name},
              'myvalue': {'S': alias}
           }
    ddb.put_item(TableName = tableName, Item = item)