diff --git a/.github/workflows/python-package.yml b/.github/workflows/python-package.yml
index 0fd714b..e1ad68e 100644
--- a/.github/workflows/python-package.yml
+++ b/.github/workflows/python-package.yml
@@ -15,7 +15,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        python-version: [3.5, 3.6, 3.7, 3.8]
+        python-version: [2.7, 3.5, 3.6, 3.7, 3.8]
 
     steps:
     - uses: actions/checkout@v2
diff --git a/lighttree/interactive.py b/lighttree/interactive.py
index 5d489d5..0576251 100644
--- a/lighttree/interactive.py
+++ b/lighttree/interactive.py
@@ -192,7 +192,7 @@ def __getitem__(self, item):
             r._expand_attrs(depth=1)
         return r
 
-    def __str__(self):
+    def _show(self):
         tree_repr = self._tree.show()
         if self._root_path is None:
             return "<%s>\n%s" % (
@@ -205,3 +205,6 @@ def __str__(self):
             text(current_path),
             text(tree_repr),
         )
+
+    def __str__(self):
+        return self._show()
diff --git a/tests/test_interactive.py b/tests/test_interactive.py
index 311e074..133a785 100644
--- a/tests/test_interactive.py
+++ b/tests/test_interactive.py
@@ -192,7 +192,7 @@ class InteractiveTree(TreeBasedObj):
 
         # test representations
         self.assertEqual(
-            obj.__str__(),
+            obj._show(),
             """<SomeCoolTree>
 root
 ├── a
@@ -205,7 +205,7 @@ class InteractiveTree(TreeBasedObj):
 """,
         )
         self.assertEqual(
-            a.__str__(),
+            a._show(),
             """<SomeCoolTree subpart: a>
 a
 ├── a1
@@ -215,7 +215,7 @@ class InteractiveTree(TreeBasedObj):
 """,
         )
         self.assertEqual(
-            a.a1.__str__(),
+            a.a1._show(),
             """<SomeCoolTree subpart: a.a1>
 a1
 ├── a11