How to fix error where a KerasTensor is passed to a TF API?

I solved the problem disabling eager execution

from tensorflow.python.framework.ops import disable_eager_execution

disable_eager_execution()

I also read some answers which suggested that this problem might be due to numpy 1.20>= , If the solution above doesn't work try downgrading numpy to like 1.19.5

Strangely by removing some imports and using entire import whenever necessary solves the issue

from tensorflow.keras.datasets import mnist
from tensorflow.keras.layers import Concatenate # _Merge
from tensorflow.keras.layers import Input, Dense, Reshape, Flatten, Dropout
from tensorflow.keras.layers import BatchNormalization, Activation, ZeroPadding2D
from tensorflow.keras.layers import LeakyReLU
from tensorflow.keras.layers import Conv2D, Conv2DTranspose, UpSampling2D
from tensorflow.keras.models import Sequential, Model
from tensorflow.keras.optimizers import RMSprop