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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 infer_from_frame_stack(self, ob_stack):
 """Infer policy from stack of observations. Args: ob_stack: array of shape (1, frame_stack_size, height, width, channels) Returns: logits and vf. """

    logits, vf = self.sess.run([self.logits_t, self.value_function_t],
                               feed_dict={self.obs_t: ob_stack})
    return logits, vf