[pre-commit.ci] auto fixes from pre-commit.com hooks

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notebooks/4-developer.ipynb

@@ -71,7 +71,7 @@
     "    command: list, universal_newlines: bool = True, shell: bool = False\n",
     "):\n",
     "    import subprocess\n",
-    "    \n",
+    "\n",
     "    return subprocess.check_output(\n",
     "        command, universal_newlines=universal_newlines, shell=shell\n",
     "    )"
@@ -158,6 +158,7 @@
    "source": [
     "def init_process():\n",
     "    import subprocess\n",
+    "\n",
     "    return {\n",
     "        \"process\": subprocess.Popen(\n",
     "            [\"python\", \"count.py\"],\n",