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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 rpc_get_refactor_options(self, filename, start, end=None):
 """Return a list of possible refactoring options. This list will be filtered depending on whether it's applicable at the point START and possibly the region between START and END. """

        try:
            from elpy import refactor
        except:
            raise ImportError("Rope not installed, refactorings unavailable")
        ref = refactor.Refactor(self.project_root, filename)
        return ref.get_refactor_options(start, end)