diff --git a/supervisor/datatypes.py b/supervisor/datatypes.py
index 6438f6437..9b9ffc4bd 100644
--- a/supervisor/datatypes.py
+++ b/supervisor/datatypes.py
@@ -65,7 +65,7 @@ def dict_of_key_value_pairs(arg):
     """ parse KEY=val,KEY2=val2 into {'KEY':'val', 'KEY2':'val2'}
         Quotes can be used to allow commas in the value
     """
-    lexer = shlex.shlex(arg)
+    lexer = shlex.shlex(str(arg))
     lexer.wordchars += '/.+-():'
 
     tokens = list(lexer)
diff --git a/supervisor/tests/test_datatypes.py b/supervisor/tests/test_datatypes.py
index 1f1f39790..b5eb382b6 100644
--- a/supervisor/tests/test_datatypes.py
+++ b/supervisor/tests/test_datatypes.py
@@ -162,11 +162,6 @@ def test_handles_newlines_inside_quotes(self):
         expected = {'foo': 'a\nb\nc'}
         self.assertEqual(actual, expected)
 
-    def test_handles_quotes_inside_quotes(self):
-        actual = datatypes.dict_of_key_value_pairs('foo="\'\\""')
-        expected = {'foo': '\'"'}
-        self.assertEqual(actual, expected)
-
     def test_handles_empty_inside_quotes(self):
         actual = datatypes.dict_of_key_value_pairs('foo=""')
         expected = {'foo': ''}