_Py_block_ty defines four types of block, FunctionBlock, ClassBlock, ModuleBlock and AnnotationBlock.
But _symtable_entry.ste_type only comments three of them, I think it's better both sides are consistent.
PyObject *ste_varnames; /* list of function parameters */
PyObject *ste_children; /* list of child blocks */
PyObject *ste_directives;/* locations of global and nonlocal statements */
- _Py_block_ty ste_type; /* module, class or function */
+ _Py_block_ty ste_type; /* module, class, function or annotation */
int ste_nested; /* true if block is nested */
unsigned ste_free : 1; /* true if block has free variables */
unsigned ste_child_free : 1; /* true if a child block has free vars,