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 Following Harvard's CS153 compiler class
 
 Link from Harvard: https://canvas.harvard.edu/courses/124796
-Link from UPenn: https://www.seas.upenn.edu/~cis5521/current/
+Link from UPenn (past, all homeworks): https://www.seas.upenn.edu/~cis3410/current
+Link from UPenn (current): https://www.seas.upenn.edu/~cis5521/current/
 Another alternative link: https://ilyasergey.net/CS4212/