diff --git a/PCP_06_complex.ipynb b/PCP_06_complex.ipynb
index 7f0fbda..42cffb5 100644
--- a/PCP_06_complex.ipynb
+++ b/PCP_06_complex.ipynb
@@ -545,8 +545,8 @@
     "<ul>\n",
     "    <li>Model the Mandelbrot set as a binary indicator function $\\chi:\\mathbb{C}\\in\\{0,1\\}$, where $\\chi(c)=1$ if $c$ belongs to the Mandelbrot set and $\\chi(c)=0$ otherwise. </li>\n",
     "    <li>Only consider complex numbers $c=a+ib$ on a discrete grid on a bounded range. It suffices to consider the range $a\\in[-2,1]$ and $b\\in[-1.2,1.2]$. Furthermore, for efficiency reasons, use a grid spacing that is not too fine. First, try out $\\Delta a = \\Delta b = 0.01$. To create the grid, you may use the function <code>np.meshgrid</code>.</li>\n",
-    "    <li>Test for each $c=a+ib$ on that grid, if $(v_c(k))_{k\\in\\mathbb{N}}$ remains bounded or not. Computationally, this cannot be tested easily. However, usually, the sequence $(v_c(k))$ increases in an exponential fashion in the case that it is not bounded. Therefore, a pragmatic (yet not always correct) test is to fix a maximum number of iterations (e.g., $K = 50$) and a threshold (e.g., $L = 100$). In case that $v_c(K)<L$, assume that the sequence is bounded and set $\\chi(c)=1$, otherwise  $\\chi(c)=0$.</li>\n",
-    "    <li>Plot $\\chi$ using the function <code>np.imshow</code>, use the colormap <code>'gray_r'</code>. Furthermore, use the parameter <code>extent</code> to adjust ranges of the horizontal axis $[-2,1]$ (real part) and vertical axis $[-1.2,1.2]$ (imaginary part).</li>           \n",
+    "    <li>Test for each $c=a+ib$ on that grid, if $(v_c(k))_{k\\in\\mathbb{N}}$ remains bounded or not. Computationally, this cannot be tested easily. However, usually, the sequence $(v_c(k))$ increases in an exponential fashion in the case that it is not bounded. Therefore, a pragmatic (yet not always correct) test is to fix a maximum number of iterations (e.g., $K = 50$) and a threshold (e.g., $L = 100$).</li>\n",
+    "    <li>Plot $\\chi$ using the function <code>plt.imshow</code>, use the colormap <code>'gray_r'</code>. Furthermore, use the parameter <code>extent</code> to adjust ranges of the horizontal axis $[-2,1]$ (real part) and vertical axis $[-1.2,1.2]$ (imaginary part).</li>           \n",
     "</ul>    \n",
     "</div>"
    ]
@@ -593,7 +593,7 @@
  "metadata": {
   "anaconda-cloud": {},
   "kernelspec": {
-   "display_name": "Python 3",
+   "display_name": "Python 3 (ipykernel)",
    "language": "python",
    "name": "python3"
   },
@@ -607,7 +607,7 @@
    "name": "python",
    "nbconvert_exporter": "python",
    "pygments_lexer": "ipython3",
-   "version": "3.9.17"
+   "version": "3.9.18"
   }
  },
  "nbformat": 4,