Update import path for available_cpus helper function

Author: AnesBenmerzoug

notebooks/shapley_basic_spotify.ipynb

@@ -95,12 +95,12 @@
    "source": [
     "from pydvl.reporting.plots import plot_shapley\n",
     "from pydvl.utils import (\n",
-    "    available_cpus,\n",
     "    load_spotify_dataset,\n",
     "    Dataset,\n",
     "    GroupedDataset,\n",
     "    Utility,\n",
     ")\n",
+    "from pydvl.utils.parallel.backend import available_cpus\n",
     "from pydvl.value.shapley import compute_shapley_values"
    ]
   },

notebooks/shapley_utility_learning.ipynb

@@ -149,8 +149,8 @@
     "    Utility,\n",
     "    DataUtilityLearning,\n",
     "    top_k_value_accuracy,\n",
-    "    available_cpus,\n",
     ")\n",
+    "from pydvl.utils.parallel.backend import available_cpus\n",
     "from pydvl.reporting.plots import shaded_mean_std\n",
     "from pydvl.value.shapley import compute_shapley_values"
    ]