MAINT: Use print functions in KdV.ipynb.

Author: WarrenWeckesser

ipython/KdV.ipynb

@@ -88,11 +88,11 @@
       "    T = 200\n",
       "    t = np.linspace(0, T, 501)\n",
       "\n",
-      "    print \"Computing the solution.\"\n",
+      "    print(\"Computing the solution.\")\n",
       "    sol = kdv_solution(u0, t, L)\n",
       "\n",
       "\n",
-      "    print \"Plotting.\"\n",
+      "    print(\"Plotting.\")\n",
       "\n",
       "    import matplotlib.pyplot as plt\n",
       "\n",