Cannot `import name '_Merge' from 'keras.layers.merge`' in Tensorflow2

Question

I am trying to run the following code on an environment which has Tensorflow 2 installed:

from keras.layers.merge import _Merge

class RandomWeightedAverage(_Merge):
"""Provides a (random) weighted average between real and generated image samples"""
def _merge_function(self, inputs):
    global batch_size
    alpha = K.random_uniform((batch_size, 1, 1, 1))
    return (alpha * inputs[0]) + ((1 - alpha) * inputs[1])

I get the following error:

ImportError: cannot import name '_Merge' from 'keras.layers.merge'

How should I modify the code to be compatible with Tensorflow2?