Port over some recent decompyle3 3.8 fixes

uncompyle6/semantics/consts.py

@@ -50,14 +50,15 @@ NO_PARENTHESIS_EVER = 100
 # fmt: off
 PRECEDENCE = {
     "named_expr":             40,  # :=
-    "yield":                  38,  # Needs to be below named_expr
-    "yield_from":             38,
-    "tuple_list_starred":     38,  # *x, *y, *z - about at the level of yield?
     "dict_unpack":            38,  # **kwargs
     "list_unpack":            38,  # *args
+    "yield_from":             38,
+    "tuple_list_starred":     38,  # *x, *y, *z - about at the level of yield?
 
     "_lambda_body":           30,
-    "lambda_body":            30,  # lambda ... : lambda_body
+    "lambda_body":            32,  # lambda ... : lambda_body
+
+    "yield":                  30,  # Needs to be below named_expr and lambda_body
 
     "if_exp":                 28,  # IfExp ( a if x else b)
     "if_exp_lambda":          28,  # IfExp involving a lambda expression

uncompyle6/semantics/customize38.py

@@ -66,6 +66,9 @@ def customize_for_version38(self, version):
                 (1, "c_suite_stmts_opt"),
                 (-2, "c_suite_stmts_opt"),
             ),
+            # Python 3.8 reverses the order of keys and items
+            # from all prior versions of Python.
+            "dict_comp_body": ("%c: %c", (0, "expr"), (1, "expr"),),
             "except_cond1a": ("%|except %c:\n", (1, "expr"),),
             "except_cond_as": (
                 "%|except %c as %c:\n",

uncompyle6/semantics/gencomp.py

@@ -302,6 +302,9 @@ class ComprehensionMixin:
             store = set_iter_async[1]
             assert store == "store"
             n = set_iter_async[2]
+        elif node == "list_comp" and tree[0] == "expr":
+            tree = tree[0][0]
+            n = tree[iter_index]
         else:
             n = tree[iter_index]