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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 full_parent_name(self):
 """Retrieves the fully qualified parent command name. This the base command name required to execute it. For example, in ``?one two three`` the parent name would be ``one two``. """

        entries = []
        command = self
        while command.parent is not None:
            command = command.parent
            entries.append(command.name)

        return ' '.join(reversed(entries))