keras: Attribute Error: Custom Generator object has no attribute 'shape'

I am using a custom data generator, when I try using fit_generator it throws an error saying “object has no attribute ‘shape’”. This is being run on a Google Colab environment.

I followed this simple tutorial for the implementation of the generator: https://medium.com/datadriveninvestor/keras-training-on-large-datasets-3e9d9dbc09d4

Data is being inputted as a list.

Tensorflow version: 1.13 Keras version: 2.2.4

Error: /usr/local/lib/python2.7/dist-packages/tensorflow/python/keras/engine/training.pyc in fit_generator(self, generator, steps_per_epoch, epochs, verbose, callbacks, validation_data, validation_steps, class_weight, max_queue_size, workers, use_multiprocessing, shuffle, initial_epoch) 1424 use_multiprocessing=use_multiprocessing, 1425 shuffle=shuffle, -> 1426 initial_epoch=initial_epoch) 1427 1428 def evaluate_generator(self,

/usr/local/lib/python2.7/dist-packages/tensorflow/python/keras/engine/training_generator.pyc in model_iteration(model, data, steps_per_epoch, epochs, verbose, callbacks, validation_data, validation_steps, class_weight, max_queue_size, workers, use_multiprocessing, shuffle, initial_epoch, mode, batch_size, **kwargs) 113 batch_size=batch_size, 114 epochs=epochs - initial_epoch, –> 115 shuffle=shuffle) 116 117 do_validation = validation_data is not None

/usr/local/lib/python2.7/dist-packages/tensorflow/python/keras/engine/training_generator.pyc in convert_to_generator_like(data, batch_size, steps_per_epoch, epochs, shuffle) 375 376 # Create generator from NumPy or EagerTensor Input. –> 377 num_samples = int(nest.flatten(data)[0].shape[0]) 378 if batch_size is None: 379 raise ValueError(‘You must specify batch_size’)

AttributeError: ‘MY_Generator’ object has no attribute ‘shape’

gist: https://gist.github.com/fjur/2815f235f84b8b666107207599482428