fix import

Author: benman1

chapter11/Ranking_with_Bandits.ipynb

@@ -119,7 +119,7 @@
    "source": [
     "# setting up the bandits:\n",
     "from mab_ranking.bandits.rank_bandits import IndependentBandits\n",
-    "from mab_ranking.bandits.bandits import BetaThompsonSampling\n",
+    "from mab_ranking.bandits.bandits import BetaThompsonSampling, DirichletThompsonSampling\n",
     "\n",
     "independent_bandits = IndependentBandits(\n",
     "    num_arms=jester_data.shape[1],\n",