diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 96751db..ff7dc53 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -122,6 +122,10 @@ jobs:
 
     -   name: Setup `g16wfx`
         run: verdi code create core.code.installed -n --config .github/config/code-gwfx.yaml --filepath-executable /Users/chemlab/Desktop/g16/g16
+
+    -   name: Setup groups
+        run: verdi group create inp_frag
+
   docs:
     runs-on: ubuntu-latest
     timeout-minutes: 15
diff --git a/aiida_aimall/calculations.py b/aiida_aimall/calculations.py
index 19e1c2a..c99944f 100644
--- a/aiida_aimall/calculations.py
+++ b/aiida_aimall/calculations.py
@@ -356,4 +356,4 @@ def _render_input_string_from_params(cls, parameters, structure_string):
         parameters.setdefault("spin_multiplicity", parameters.pop("multiplicity", None))
         parameters["title"] = "input generated by the aiida-gaussian plugin"
         gaussian_input = GaussianInput(structure_string, **parameters)
-        return gaussian_input.to_string(cart_coords=True)
+        return gaussian_input.to_str(cart_coords=True)
diff --git a/tests/controllers/test_g16fragcontroller.py b/tests/controllers/test_g16fragcontroller.py
index a56da9f..3655ca9 100644
--- a/tests/controllers/test_g16fragcontroller.py
+++ b/tests/controllers/test_g16fragcontroller.py
@@ -1,7 +1,7 @@
 """Tests for aiida_aimall.controllers"""
 import pytest
 from aiida.common.exceptions import NotExistent
-from aiida.orm import Group, Str
+from aiida.orm import Str
 
 # pylint:disable=no-name-in-module
 from aiida_aimall.controllers import G16FragController
@@ -14,7 +14,7 @@ def test_unstored_parentgrouplabel_returns_error():
     """Test that error returns when groups are not defined"""
     with pytest.raises(NotExistent) as excinfo:
         G16FragController(
-            parent_group_label="inp_frag",
+            parent_group_label="empty",
             group_label="opt_workchain",
             max_concurrent=1,
             code_label="test.aimall.aimqb",
@@ -25,10 +25,7 @@ def test_unstored_parentgrouplabel_returns_error():
 
 def test_g16frag_controller():
     """Test that error returns when groups are not defined"""
-    gr = Group(label="opt_workchain")
-    gr.store()
-    gr = Group(label="inp_frag")
-    gr.store()
+
     # with pytest.raises(NotExistent) as excinfo:
     con = G16FragController(
         parent_group_label="inp_frag",