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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 invalid_index(self, name):
 """Show an invalid index error message."""

        self.stderr.write("Unknown index: {}".format(name))
        self.stderr.write("Supported indices are:")
        for index in index_builder.indexes:
            self.stderr.write("  * {}".format(index.__class__.__name__))