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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 delete_show_function(self, show_name):
 """ Removes an existing show function in the locally cached DesignDocument shows dictionary. :param show_name: Name used to identify the list. """

        if self.get_show_function(show_name) is None:
            return

        self.shows.__delitem__(show_name)