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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_index(self, index_name):
 """ Removes an existing index in the locally cached DesignDocument indexes dictionary. :param str index_name: Name used to identify the index. """

        index = self.get_index(index_name)
        if index is None:
            return

        self.indexes.__delitem__(index_name)