refactor: use enum to specify type

bridge/reply.py

@@ -0,0 +1,22 @@
+
+# encoding:utf-8
+
+from enum import Enum
+
+class ReplyType(Enum):
+    TEXT = 1        # 文本
+    VOICE = 2       # 音频文件
+    IMAGE = 3       # 图片文件
+    IMAGE_URL = 4   # 图片URL
+    
+    INFO = 9
+    ERROR = 10
+    def __str__(self):
+        return self.name
+
+class Reply:
+    def __init__(self, type : ReplyType = None , content = None):
+        self.type = type
+        self.content = content
+    def __str__(self):
+        return "Reply(type={}, content={})".format(self.type, self.content)