link to google colab for lessons 2 and 3 and the solutions

[rbarreto]

can we get a link to the google colab in lessons 2 and 3 and the solutions? we had to put the repo url into google collab

[rbarreto]

link for lesson 1 is in the notebook
here's the link for lesson 2: https://colab.research.google.com/github/dlab-berkeley/Python-Deep-Learning/blob/main/lessons/02-Vanilla-Convolutional-Neural-Network-Comparison.ipynb