From 23f8e01cf9e712ed823532fefc0768e321aadd08 Mon Sep 17 00:00:00 2001
From: HJW20 <1264519711@qq.com>
Date: Tue, 24 Jun 2025 11:36:44 +0800
Subject: [PATCH] 1

---
 面向对象学生系统/Dal/find_students_by_sid.py | 6 ++++++
 1 file changed, 6 insertions(+)
 create mode 100644 面向对象学生系统/Dal/find_students_by_sid.py

diff --git a/面向对象学生系统/Dal/find_students_by_sid.py b/面向对象学生系统/Dal/find_students_by_sid.py
new file mode 100644
index 0000000..18ab8a1
--- /dev/null
+++ b/面向对象学生系统/Dal/find_students_by_sid.py
@@ -0,0 +1,6 @@
+def find_student_by_sid(self,sid:str)-> Optional[Student]:
+    students =self.load_students()
+    for student in students:
+        if student.sid==sid:
+            return student
+    return None
\ No newline at end of file