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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def message_handler(self, commands=None, regexp=None, func=None, content_types=['text'], **kwargs):
 """ Message handler decorator. This decorator can be used to decorate functions that must handle certain types of messages. All message handlers are tested in the order they were added. Example: bot = TeleBot('TOKEN') # Handles all messages which text matches regexp. @bot.message_handler(regexp='someregexp') def command_help(message):
 bot.send_message(message.chat.id, 'Did someone call for help?') # Handle all sent documents of type 'text/plain'. @bot.message_handler(func=lambda message: message.document.mime_type == 'text/plain', content_types=['document']) def command_handle_document(message):
 bot.send_message(message.chat.id, 'Document received, sir!') # Handle all other commands. @bot.message_handler(func=lambda message: True, content_types=['audio', 'video', 'document', 'text', 'location', 'contact', 'sticker']) def default_command(message):
 bot.send_message(message.chat.id, "This is the default command handler.") :param regexp: Optional regular expression. :param func: Optional lambda function. The lambda receives the message to test as the first parameter. It must return True if the command should handle the message. :param content_types: This commands' supported content types. Must be a list. Defaults to ['text']. """


        def decorator(handler):
            handler_dict = self._build_handler_dict(handler,
                                                    commands=commands,
                                                    regexp=regexp,
                                                    func=func,
                                                    content_types=content_types,
                                                    **kwargs)

            self.add_message_handler(handler_dict)

            return handler

        return decorator