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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 _process_pending_variables(self):
 """ Try to apply the variables that were set but not known yet. """

        # Clear our list of pending variables
        self._pending_variables, pending = {}, self._pending_variables
        # Try to apply it. On failure, it will be added again
        for name, data in pending.items():
            self[name] = data