0(1) element: null
1(2) element: PyAssertStatement
2(3) READ ACCESS: False
3(11) raise: PyAssertStatement
4(5) element: PyPrintStatement
5(6) element: PyAssertStatement
6(7) READ ACCESS: False
7(8) READ ACCESS: f
8(9) element: PyCallExpression: f
9(11) raise: PyAssertStatement
10(11) element: PyPrintStatement
11() element: null