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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 drop_message(self, message):
 """Drop the given message object from the appropriate message list. Returns True if the message was found, otherwise False."""


        for type_ in 'errors', 'warnings', 'notices':
            list_ = getattr(self, type_)
            if message in list_:
                list_.remove(message)
                if 'signing_severity' in message:
                    self.signing_summary[message['signing_severity']] -= 1
                return True

        return False