minor fix

邮件批量发送脚本.py

@@ -263,11 +263,7 @@ def main():
         code = codes[current]
         mark = sents[current]
 
-        if not code:
-            print(f'[警告] 最大允许重复次数已设置为 [{args.max_occurrence}], 但未提供有效唯一标识 (如客户编号)')
-            occurrence = [0]
-        else:
-            occurrence = occurrences.setdefault(code, [0])
+        occurrence = occurrences.setdefault(code, [0]) if code else [0]
 
         if mark is not None and str(mark).strip():
             print(f'[信息] 已跳过项目 {recipient}')