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matplotlib.ipynb

@@ -1131,6 +1131,7 @@
       "\n",
       "**Hint 2:** Have a look at the `cumsum` function.\n",
       "\n",
+      "* Does the walk actually start from (0, 0, 0)? If not, do you know how to fix it?\n",
       "* Graphically indicate the start and end of the sequence.\n",
       "* Try to find some interesting DNA sequences to visualise (e.g., containing some repeat sequences)."
      ]