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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 change_name(self, new_name):
 """Change the name of the shell, possibly updating the maximum name length"""

        if not new_name:
            name = self.hostname
        else:
            name = new_name.decode()
        self.display_name = display_names.change(
            self.display_name, name)