Lambda terms in de Bruijn notation are represented as trees with unary lambda nodes and binary application nodes, with de Bruijn indices (starting at 0) marking their leaf nodes. Write a Python program, that given a lambda term in de Bruijn notation, displays it as a tree. The program must use Python tuples for both our lambda nodes and application nodes. To facilitate testing with easier to read inputs, we define: def l(x) : return ('l',x) def a(x,y) : return ('a',x,y) As an example, the Python expression l(l(a(a(0,l(3)),a(l(0),0)))) returns the tree ('l', ('l', ('a', ('a', 0, ('l', 3)), ('a', ('l', 0), 0)))) that can be displayed like this: l | | l | | a __|_ / \ a a | | / \ / \ 0 l l 0 | | | | 3 0 While you can choose to write your own algorithm that outputs the tree using ASCII characters as in the picture above, you can also opt for using any of the available Python packages to help drawing nicer looking trees. Test set. l(a(a(1,a(l(l(0)),1)),1)) l(l(l(l(a(0,a(1,l(l(a(0,a(2,0)))))))))) l(l(l(a(a(0,a(1,a(a(l(l(0)),0),2))),1)))) l(l(l(a(l(1),a(l(a(1,0)),a(a(a(2,0),0),0)))))) l(l(l(a(l(a(2,a(a(l(0),l(a(1,a(1,a(1,l(1)))))),l(0)))),a(2,0)))))