将下面任务中的T-SQL代码形成一个脚本：在test_db数据库中创建表person并插入如下元祖, 使用整型局部变量mycount统计person中的行数，并将其另命名为数据表中的行数。

Sure! Here's the T-SQL script to create the table "person" in the "test_db" database, insert the given tuples, and use a local integer variable "mycount" to count the number of rows in the "person" table and assign it to a variable named "row_count".

-- Create table "person"
USE test_db;
GO

CREATE TABLE person (
    id INT,
    name VARCHAR(50),
    age INT
);

-- Insert tuples into "person" table
INSERT INTO person (id, name, age)
VALUES
    (1, 'John', 25),
    (2, 'Sarah', 30),
    (3, 'Michael', 35);

-- Use local variable to count rows in "person" table
DECLARE @mycount INT;
SELECT @mycount = COUNT(*) FROM person;

-- Assign the row count to a variable named "row_count"
DECLARE @row_count INT;
SET @row_count = @mycount;

-- Display the row count
SELECT @row_count AS [Row Count];

Please note that this script assumes you have the necessary permissions to create a table and insert data into the database. Adjust the script accordingly if needed.