diff --git a/docs/lambda-k-pi/ampform-dpd.ipynb b/docs/lambda-k-pi/ampform-dpd.ipynb
index 40b351e..51635bd 100644
--- a/docs/lambda-k-pi/ampform-dpd.ipynb
+++ b/docs/lambda-k-pi/ampform-dpd.ipynb
@@ -57,9 +57,7 @@
     "from ampform_dpd.io import aslatex\n",
     "from IPython.display import SVG, Image, Markdown, Math, display\n",
     "from qrules.particle import Particle, Spin, create_particle, load_pdg\n",
-    "from tensorwaves.data import (\n",
-    "    SympyDataTransformer,\n",
-    ")\n",
+    "from tensorwaves.data import SympyDataTransformer\n",
     "from tensorwaves.function.sympy import create_parametrized_function\n",
     "\n",
     "STATIC_PAGE = \"EXECUTE_NB\" in os.environ\n",