Update app.py

app.py

@@ -253,7 +253,7 @@ def classify_email(json_input):
 # ===================== 核心处理函数（模拟邮件分析） =====================
 def classify_email(sender: str, subject: str, body: str) -> tuple[str, str]:
     if sender.strip() ==  "" or subject.strip() == "" or body.strip() == "" :
-        return return "true", "sender、subject、subject为空"
+        return "true", "sender、subject、subject为空"
         
     email = {
         "sender": sender,