diff --git a/astmonkey/tests/test_visitors.py b/astmonkey/tests/test_visitors.py
index d060646..12ddec8 100644
--- a/astmonkey/tests/test_visitors.py
+++ b/astmonkey/tests/test_visitors.py
@@ -137,6 +137,7 @@ class TestSourceGeneratorNodeVisitor(object):
         'y * (z if z > 1 else 1)',
         'if x < y == z < x:' + EOL + INDENT + PASS,
         'if (x < y) == (z < x):' + EOL + INDENT + PASS,
+        'if not False:' + EOL + INDENT + PASS,
         'if x:' + EOL + INDENT + PASS + EOL + EOL + 'elif x:' + EOL + INDENT + PASS,  # Double EOL
 
         # while
diff --git a/astmonkey/visitors.py b/astmonkey/visitors.py
index 6393c10..35d7430 100644
--- a/astmonkey/visitors.py
+++ b/astmonkey/visitors.py
@@ -674,7 +674,7 @@ def visit_UnaryOp(self, node):
                 self.write(' ')
 
             with self.inside('(', ')', cond=(not isinstance(node.operand, (ast.Name, ast.Num))
-                                             and not self._is_named_constant(node))):
+                                             and not self._is_named_constant(node.operand))):
                 self.visit(node.operand)
 
     def visit_Subscript(self, node):
@@ -836,7 +836,7 @@ def with_body(self, node, prefixes=[]):
 
     @staticmethod
     def _is_named_constant(node):
-        return isinstance(node, ast.Expr) and hasattr(node, value) and isinstance(node.value, ast.Name)
+        return isinstance(node, ast.Expr) and hasattr(node, 'value') and isinstance(node.value, ast.Name)
 
 
 class SourceGeneratorNodeVisitorPython26(BaseSourceGeneratorNodeVisitor):