DataFrame: employees
+-------------+--------+
| Column Name | Type   |
+-------------+--------+
| employee_id | int    |
| name        | object |
| department  | object |
| salary      | int    |
+-------------+--------+

编写一个解决方案，显示这个 DataFrame 的 前  3 行。

示例 1:

输入：
DataFrame employees
+-------------+-----------+-----------------------+--------+
| employee_id | name      | department            | salary |
+-------------+-----------+-----------------------+--------+
| 3           | Bob       | Operations            | 48675  |
| 90          | Alice     | Sales                 | 11096  |
| 9           | Tatiana   | Engineering           | 33805  |
| 60          | Annabelle | InformationTechnology | 37678  |
| 49          | Jonathan  | HumanResources        | 23793  |
| 43          | Khaled    | Administration        | 40454  |
+-------------+-----------+-----------------------+--------+
输出：
+-------------+---------+-------------+--------+
| employee_id | name    | department  | salary |
+-------------+---------+-------------+--------+
| 3           | Bob     | Operations  | 48675  |
| 90          | Alice   | Sales       | 11096  |
| 9           | Tatiana | Engineering | 33805  |
+-------------+---------+-------------+--------+
解释：
只有前 3 行被显示。