Tensorflow を用いて、AdaGrad を実装してください．
learning_rate = 5e-1
momentum = 0.9
Ada_optimizer = ##########
1. tf.train.Afagradoptimizer(momentum=momentum, learning_rate = learning_rate)
2. tf.train.AdagradOptimizer(learning_rate=learning_rate)
3. tf.train.AdagradOptimizer(momentum=momentum)