bpo-39882: Add _Py_FatalErrorFormat() function (GH-19157)

diff --git a/Python/ast.c b/Python/ast.c
index 2b74ed4..fb23c02 100644
--- a/Python/ast.c
+++ b/Python/ast.c
@@ -727,11 +727,8 @@
                 return l;
             }
         default: {
-            char buf[128];
-
-            sprintf(buf, "Non-statement found: %d %d",
-                    TYPE(n), NCH(n));
-            Py_FatalError(buf);
+            _Py_FatalErrorFormat(__func__, "Non-statement found: %d %d",
+                                 TYPE(n), NCH(n));
         }
     }
     Py_UNREACHABLE();
@@ -1664,7 +1661,7 @@
     REQ(n, decorator);
     REQ(CHILD(n, 0), AT);
     REQ(CHILD(n, 2), NEWLINE);
-    
+
     return ast_for_expr(c, CHILD(n, 1));
 }