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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 get_summary_string(self):
 """Get a string summarising the state of Rez as a whole. Returns: String. """

        from rez.plugin_managers import plugin_manager

        txt = "Rez %s" % __version__
        txt += "\n\n%s" % plugin_manager.get_summary_string()
        return txt