TASK: Add own message filters

Author: Rico

own_filters.py

@@ -0,0 +1,15 @@
+from telegram.ext import BaseFilter
+
+
+# A filter which returns True, if a message is sent in an allowed group and False if not.
+class _ChannelFilter(BaseFilter):
+    name = "ChannelFilter"
+
+    def filter(self, message):
+        if message.chat.type == "channel":
+            return True
+
+        return False
+
+
+ChannelFilter = _ChannelFilter()