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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 is_root_path(self, filename):
 """Determines if 'filename' corresponds to a directory on this device."""

        test_filename = filename + '/'
        for root_dir in self.root_dirs:
            if test_filename.startswith(root_dir):
                return True
        return False