fix name

Author: tdhopper

Examples.ipynb

@@ -1191,7 +1191,7 @@
    "outputs": [],
    "source": [
     "%%altair \n",
-    "(altair\n",
+    "(alt\n",
     " .Chart(mpg)\n",
     " .mark_circle()\n",
     " .encode(x=\"displ\", y=\"hwy\",)\n",