0(1) element: null
1(2) element: PyMatchStatement
2(3,9) WRITE ACCESS: x
3(4,5) READ ACCESS: x
4(9) element: null. Condition: x > 0:false
5(6) element: null. Condition: x > 0:true
6(7) element: PyStatementList
7(8) element: PyExpressionStatement
8(10) READ ACCESS: y
9(10) ASSERTTYPE ACCESS: null
10(11) element: PyExpressionStatement
11(12) READ ACCESS: z
12() element: null