0(1) element: null
1(2) element: PyMatchStatement
2(3,11) refutable pattern: [1, *x]
3(4,11) refutable pattern: 1
4(5) matched pattern: 1
5(6,11) element: PySingleStarPattern
6(7,11) WRITE ACCESS: x
7(8) matched pattern: [1, *x]
8(9) element: PyStatementList
9(10) element: PyExpressionStatement
10(12) READ ACCESS: y
11(12) ASSERTTYPE ACCESS: null
12(13) element: PyExpressionStatement
13(14) READ ACCESS: z
14() element: null