kaitai tests translator python

git.diff

diff --git a/translator/src/main/scala/io/kaitai/struct/testtranslator/specgenerators/PythonSG.scala b/translator/src/main/scala/io/kaitai/struct/testtranslator/specgenerators/PythonSG.scala
index 327d3df0..0b64d616 100644
--- a/translator/src/main/scala/io/kaitai/struct/testtranslator/specgenerators/PythonSG.scala
+++ b/translator/src/main/scala/io/kaitai/struct/testtranslator/specgenerators/PythonSG.scala
@@ -56,7 +56,9 @@ class PythonSG(spec: TestSpec, provider: ClassTypeProvider) extends BaseGenerato
 
   override def nullAssert(actual: Ast.expr): Unit = {
     val actStr = translateAct(actual)
-    out.puts(s"self.assertIsNone($actStr)")
+    val attrStr = actStr.substring(actStr.lastIndexOf('.') + 1)
+    val inStr = actStr.substring(0, actStr.lastIndexOf('.'))
+    out.puts(s"""self.assertIsNone($actStr if hasattr($inStr, "$attrStr") else None)""")
   }
 
   override def trueArrayAssert(check: TestAssert, elType: DataType, elts: Seq[Ast.expr]): Unit =