Remove some Python 3.6 references

test/failing_examples.py

@@ -34,7 +34,7 @@ FAILING_EXAMPLES = [
     'lambda x=3, y: x',
     '__debug__ = 1',
     'with x() as __debug__: pass',
-    # Mostly 3.6 relevant
+
     '[]: int',
     '[a, b]: int',
     '(): int',

test/test_error_recovery.py

@@ -74,7 +74,7 @@ def test_invalid_token():
 
 
 def test_invalid_token_in_fstr():
-    module = load_grammar(version='3.6').parse('f"{a + ? + b}"')
+    module = load_grammar(version='3.9').parse('f"{a + ? + b}"')
     error_node, q, plus_b, error1, error2, endmarker = module.children
     assert error_node.get_code() == 'f"{a +'
     assert q.value == '?'

test/test_tokenize.py

@@ -184,7 +184,6 @@ def test_ur_literals():
     check('bR""')
     check('Rb""')
 
-    # Starting with Python 3.6 format strings where introduced.
     check('fr""')
     check('rF""')
     check('f""')