title: Error module 'keras.optimizers' has no attribute 'RMSprop'
body: <p>I am running this code below and it returned an error AttributeError: module 'keras.optimizers' has no attribute 'RMSprop'. I download tensorflow using <code>pip install tensorflow</code>.</p>
  <pre><code>from keras import layers
  from keras import models
  
  model = models.Sequential()
  model.add(layers.Conv2D(32, (3, 3), activation='relu',
                          input_shape=(150, 150, 3)))
  model.add(layers.MaxPooling2D((2, 2)))
  model.add(layers.Conv2D(64, (3, 3), activation='relu'))
  model.add(layers.MaxPooling2D((2, 2)))
  model.add(layers.Conv2D(128, (3, 3), activation='relu'))
  model.add(layers.MaxPooling2D((2, 2)))
  model.add(layers.Conv2D(128, (3, 3), activation='relu'))
  model.add(layers.MaxPooling2D((2, 2)))
  model.add(layers.Flatten())
  model.add(layers.Dense(512, activation='relu'))
  model.add(layers.Dense(1, activation='sigmoid'))
  
  model.summary()
  
  from keras import optimizers
  
  model.compile(loss='binary_crossentropy', optimizer=optimizers.RMSprop(lr=1e-4), metrics=['acc'])
  </code></pre>
  <p>Could anyone please help explain to me what's wrong with this? Thank you for your time.</p>