Avoid a crash when unpickling certain parse trees generated using html5lib on Python 3. [bug=1843545]

2 files changed, 5 insertions, 2 deletions

diff --git a/bs4/element.py b/bs4/element.py
index d6ed020..2001ad5 100644
--- a/bs4/element.py
+++ b/bs4/element.py
@@ -45,7 +45,7 @@ def _alias(attr):
 
 class NamespacedAttribute(unicode):
 
-    def __new__(cls, prefix, name, namespace=None):
+    def __new__(cls, prefix, name=None, namespace=None):
         if not name:
             # This is the default namespace. Its name "has no value"
             # per https://www.w3.org/TR/xml-names/#defaulting
diff --git a/bs4/tests/test_soup.py b/bs4/tests/test_soup.py
index 3603e81..dc88662 100644
--- a/bs4/tests/test_soup.py
+++ b/bs4/tests/test_soup.py
@@ -638,10 +638,13 @@ class TestUnicodeDammit(unittest.TestCase):
             
 class TestNamedspacedAttribute(SoupTest):
 
-    def test_name_may_be_none(self):
+    def test_name_may_be_none_or_missing(self):
         a = NamespacedAttribute("xmlns", None)
         self.assertEqual(a, "xmlns")
 
+        a = NamespacedAttribute("xmlns")
+        self.assertEqual(a, "xmlns")
+        
     def test_attribute_is_equivalent_to_colon_separated_string(self):
         a = NamespacedAttribute("a", "b")
         self.assertEqual("a:b", a)