改进部分代码，增加Linux可运行的版本，可自己选择想要进入的房间

Signed-off-by: Jerry Yan <792602257@qq.com>

Chat.py

@@ -0,0 +1,23 @@
+from User import User
+
+class Chat:
+
+    content:str=""
+    user:User=None
+
+    def __init__(self, json=None):
+        if json:
+            self.parse(json)
+
+    def parse(self, json):
+        self.user = User(json)
+        if "Msg" in json:
+            if "content" in json["Msg"]:
+                self.content = json["Msg"]['content']
+
+    def __str__(self):
+        return "{} : {}".format(self.user,self.content)
+
+    def __unicode__(self):
+        return self.__str__()
+