looping over list to get values in another list

Question

Lets say you have two lists: list1 = [\'(18,430)\', \'(19,430)\', \'(19,429)\', \'(19,428)\', \'(19,427)\', \'(18,426)\',\'(17,426)\'] and list2 = [\'(18,430)\', \'(19,430)\