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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 rename_header(self, old_name, new_name):
 """ This will rename the header. The supplied names need to be strings. """

        self.hkeys[self.hkeys.index(old_name)] = new_name
        self.headers[new_name] = self.headers.pop(old_name)
        return self