+Looking at the node dump above, you can see that `$stmts` for this example code is an array of two
+nodes, a `Stmt_Function` and a `Stmt_Expression`. The corresponding class names are:
+
+ * `Stmt_Function -> PhpParser\Node\Stmt\Function_`
+ * `Stmt_Expression -> PhpParser\Node\Stmt\Expression`
+
+The additional `_` at the end of the first class name is necessary, because `Function` is a
+reserved keyword. Many node class names in this library have a trailing `_` to avoid clashing with
+a keyword.
+
+As PHP is a large language there are approximately 140 different nodes. In order to make working