CNN Model: Freeze Convolutional Layers

from keras.applications import MobileNet

# MobileNet was designed to work on 224 x 224 pixel input images sizes
img_rows, img_cols = 224, 224 

# Re-loads the MobileNet model without the top or FC layers
MobileNet = MobileNet(weights = 'imagenet', 
                 include_top = False, 
                 input_shape = (img_rows, img_cols, 3))

# Here we freeze the last 4 layers 
# Layers are set to trainable as True by default
for layer in MobileNet.layers:
    layer.trainable = False