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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 refactor(self, items, write=False, doctests_only=False):
 """Refactor a list of files and directories."""


        for dir_or_file in items:
            if os.path.isdir(dir_or_file):
                self.refactor_dir(dir_or_file, write, doctests_only)
            else:
                self.refactor_file(dir_or_file, write, doctests_only)