I’m confused about the homework even though I passed it. In the first part, C4_W3_Assignment, we built an Encoder from scratch which is supposedly the BERT model. In the second part, C4_W3_Assignment_Ungraded_BERT_loss (done in Colab), we took a pretrained model and used it for prediction. The pretrained model was trained on the C4 dataset I suppose. This part is fine.
In the third part, C4_W3_Assignment_Ungraded_T5, the model now is an Encoder-Decoder, correct? I suppose the model is the Encoder model we did in the first part and the Decoder model that we did in week 2 homework put together. Is this correct? However, in this third part of the homework, it says the model was fine-tuned on the SQuaD dataset. So was the T5 model originally trained on the C4 dataset and then fine-tuned on the SQuaD? What were the fine-tuning steps? Or does fine-tuning mean T5 was originally trained on C4 and it was later trained using SQuaD for a different task?