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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 parents(self):
 """Retrieves the parents of this command. If the command has no parents then it returns an empty :class:`list`. For example in commands ``?a b c test``, the parents are ``[c, b, a]``. .. versionadded:: 1.1.0 """

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

        return entries