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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 rename(self, new_name):

 """Rename project and rename its root path accordingly."""

        old_name = self.name
        self.name = new_name
        pypath = self.relative_pythonpath  # ??
        self.root_path = self.root_path[:-len(old_name)]+new_name
        self.relative_pythonpath = pypath  # ??
        self.save()