Narrow precedence for call statement

Author: rocky

uncompyle6/semantics/consts.py

@@ -327,7 +327,10 @@
     # For compatibility with older Python, we'll use "%" instead of
     # a format string.
     "string_at_beginning": ('%|"%%s" %% %c\n', 0),
-    "call_stmt": ("%|%p\n", (0, 200)),
+    "call_stmt":	   ( "%|%p\n",
+                             # When a call statement contains only a named_expr (:=)
+                             # the named_expr should have parenthesis around it.
+                             (0, PRECEDENCE["named_expr"]-1)),
     "break": ("%|break\n",),
     "continue": ("%|continue\n",),
     "raise_stmt0": ("%|raise\n",),

uncompyle6/semantics/customize37.py

@@ -149,6 +149,11 @@ def customize_for_version37(self, version):
                 (1, "store"), (0, "get_aiter"), (3, "list_iter"),
             ),
 
+            "list_afor": (
+                " async for %[1]{%c} in %c%[1]{%c}",
+                (1, "store"), (0, "get_aiter"), (3, "list_iter"),
+            ),
+
             "list_if37": (" if %p%c", (0, 27), 1),
             "list_if37_not": (" if not %p%c", (0, 27), 1),
             "testfalse_not_or": ("not %c or %c", (0, "expr"), (2, "expr")),