Do not require curly bracket in tag name

Tests/test_file_jpeg.py

@@ -898,6 +898,14 @@ class TestFileJpeg:
             with Image.open("Tests/images/hopper.jpg") as im:
                 assert im.getxmp() == {}
 
+    def test_getxmp_no_prefix(self):
+        with Image.open("Tests/images/xmp_no_prefix.jpg") as im:
+            if ElementTree is None:
+                with pytest.warns(UserWarning):
+                    assert im.getxmp() == {}
+            else:
+                assert im.getxmp() == {"xmpmeta": {"key": "value"}}
+
     def test_getxmp_padded(self):
         with Image.open("Tests/images/xmp_padded.jpg") as im:
             if ElementTree is None:

src/PIL/Image.py

@@ -1380,7 +1380,7 @@ class Image:
 
     def _getxmp(self, xmp_tags):
         def get_name(tag):
-            return tag.split("}")[1]
+            return re.sub("^{[^}]+}", "", tag)
 
         def get_value(element):
             value = {get_name(k): v for k, v in element.attrib.items()}