bug fix

Author: KoichiYasuoka

doc/af.ipynb

@@ -31,7 +31,7 @@
         "import sys\n",
         "v=\".\".join(sys.version.split(\".\")[0:2])\n",
         "!update-alternatives --remove-all python3\n",
-        "!update-alternatives --install /usr/bin/python3 python3 /usr/bin/python3.{v} 1\n",
+        "!update-alternatives --install /usr/bin/python3 python3 /usr/bin/python{v} 1\n",
         "!update-alternatives --install /usr/bin/python3 python3 /usr/bin/python3.8 2\n",
         "!apt install python3-pip\n",
         "!pip install \"setuptools<57\" poetry deplacy cymem==2.0.11 preshed==3.0.10\n",