diff --git a/parso/python/grammar310.txt b/parso/python/grammar310.txt
index 11697ea..fce8753 100644
--- a/parso/python/grammar310.txt
+++ b/parso/python/grammar310.txt
@@ -124,14 +124,14 @@ atom: ('(' [yield_expr|testlist_comp] ')' |
 testlist_comp: (namedexpr_test|star_expr) ( comp_for | (',' (namedexpr_test|star_expr))* [','] )
 trailer: '(' [arglist] ')' | '[' subscriptlist ']' | '.' NAME
 subscriptlist: subscript (',' subscript)* [',']
-subscript: test | [test] ':' [test] [sliceop]
+subscript: test [':=' test] | [test] ':' [test] [sliceop]
 sliceop: ':' [test]
 exprlist: (expr|star_expr) (',' (expr|star_expr))* [',']
 testlist: test (',' test)* [',']
 dictorsetmaker: ( ((test ':' test | '**' expr)
                    (comp_for | (',' (test ':' test | '**' expr))* [','])) |
-                  ((test | star_expr)
-                   (comp_for | (',' (test | star_expr))* [','])) )
+                  ((test [':=' test] | star_expr)
+                   (comp_for | (',' (test [':=' test] | star_expr))* [','])) )
 
 classdef: 'class' NAME ['(' [arglist] ')'] ':' suite
 
diff --git a/parso/python/grammar39.txt b/parso/python/grammar39.txt
index 11697ea..f17eba5 100644
--- a/parso/python/grammar39.txt
+++ b/parso/python/grammar39.txt
@@ -130,8 +130,8 @@ exprlist: (expr|star_expr) (',' (expr|star_expr))* [',']
 testlist: test (',' test)* [',']
 dictorsetmaker: ( ((test ':' test | '**' expr)
                    (comp_for | (',' (test ':' test | '**' expr))* [','])) |
-                  ((test | star_expr)
-                   (comp_for | (',' (test | star_expr))* [','])) )
+                  ((test [':=' test] | star_expr)
+                   (comp_for | (',' (test [':=' test] | star_expr))* [','])) )
 
 classdef: 'class' NAME ['(' [arglist] ')'] ':' suite
 
diff --git a/test/failing_examples.py b/test/failing_examples.py
index c89f1f3..8f2edca 100644
--- a/test/failing_examples.py
+++ b/test/failing_examples.py
@@ -356,6 +356,10 @@ if sys.version_info[:2] >= (3, 8):
         '(False := 1)',
         '(None := 1)',
         '(__debug__ := 1)',
+        # Unparenthesized walrus not allowed in dict literals, dict comprehensions and slices
+        '{a:="a": b:=1}',
+        '{y:=1: 2 for x in range(5)}',
+        'a[b:=0:1:2]',
     ]
     # f-string debugging syntax with invalid conversion character
     FAILING_EXAMPLES += [
diff --git a/test/test_python_errors.py b/test/test_python_errors.py
index 02b1d40..fa07d66 100644
--- a/test/test_python_errors.py
+++ b/test/test_python_errors.py
@@ -289,12 +289,37 @@ def test_valid_fstrings(code):
         '[total := total + v for v in range(10)]',
         'while chunk := file.read(2):\n pass',
         'numbers = [y := math.factorial(x), y**2, y**3]',
+        '{(a:="a"): (b:=1)}',
+        '{(y:=1): 2 for x in range(5)}',
+        'a[(b:=0)]',
+        'a[(b:=0, c:=0)]',
+        'a[(b:=0):1:2]',
     ]
 )
 def test_valid_namedexpr(code):
     assert not _get_error_list(code, version='3.8')
 
 
+@pytest.mark.parametrize(
+    'code', [
+        '{x := 1, 2, 3}',
+        '{x4 := x ** 5 for x in range(7)}',
+    ]
+)
+def test_valid_namedexpr_set(code):
+    assert not _get_error_list(code, version='3.9')
+
+
+@pytest.mark.parametrize(
+    'code', [
+        'a[b:=0]',
+        'a[b:=0, c:=0]',
+    ]
+)
+def test_valid_namedexpr_index(code):
+    assert not _get_error_list(code, version='3.10')
+
+
 @pytest.mark.parametrize(
     ('code', 'message'), [
         ("f'{1+}'", ('invalid syntax')),