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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 allow_exception(self, exc_class):
 """Allow raising this class of exceptions from commands. When a command fails on the server side due to an exception, by default it is turned into a string and raised on the client side as an ExternalError. The original class name is sent but ignored. If you would like to instead raise an instance of the same exception on the client side, you can pass the exception class object to this method and instances of that exception will be reraised. The caveat is that the exception must be creatable with a single string parameter and it should have a ``msg`` property. Args: exc_class (class):
 A class object with the exception that we should allow to pass from server to client. """


        name = exc_class.__name__
        self._allowed_exceptions[name] = exc_class