Fix NameError (#59)

Author: AlbertEinsteinTG

pyrogram/types/user_and_chats/chat.py

@@ -382,7 +382,7 @@ def _parse_user_chat(client, user: raw.types.User) -> "Chat":
  def _parse_chat_chat(client, chat: raw.types.Chat) -> "Chat":
  peer_id = -chat.id
 
- if isinstance(channel, raw.types.ChatForbidden):
+ if isinstance(chat, raw.types.ChatForbidden):
  return Chat(
  id=peer_id,
  type=enums.ChatType.GROUP,