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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 _initialize_model(self):
 """ Initialize the defined network and restore from files is so specified. """

        # Initialize all variables first
        self.sess.run(tf.local_variables_initializer())
        self.sess.run(tf.global_variables_initializer())
        if self.flags['RESTORE_META'] == 1:
            print('Restoring from .meta file')
            self._restore_meta()
        elif self.flags['RESTORE_SLIM'] == 1:
            print('Restoring TF-Slim Model.')
            all_model_variables = tf.global_variables()
            self._restore_slim(all_model_variables)
        else:
            print("Model training from scratch.")