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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 add_show_function(self, show_name, show_func):
 """ Appends a show function to the locally cached DesignDocument shows dictionary. :param show_name: Name used to identify the show function. :param show_func: Javascript show function. """

        if self.get_show_function(show_name) is not None:
            raise CloudantArgumentError(110, show_name)

        self.shows.__setitem__(show_name, show_func)