diff --git a/doc/source/gallery/plotting_with_folium.ipynb b/doc/source/gallery/plotting_with_folium.ipynb
index e01574f..773d6b8 100644
--- a/doc/source/gallery/plotting_with_folium.ipynb
+++ b/doc/source/gallery/plotting_with_folium.ipynb
@@ -40,7 +40,7 @@
    "metadata": {},
    "outputs": [],
    "source": [
-    "df1 = pd.read_csv('volcano_data_2010.csv')\n",
+    "df1 = pd.read_csv(\"volcano_data_2010.csv\")\n",
     "\n",
     "# Keep only relevant columns\n",
     "df = df1.loc[:, (\"Year\", \"Name\", \"Country\", \"Latitude\", \"Longitude\", \"Type\")]\n",
@@ -55,7 +55,9 @@
    "source": [
     "# Create point geometries\n",
     "geometry = geopandas.points_from_xy(df.Longitude, df.Latitude)\n",
-    "geo_df = geopandas.GeoDataFrame(df[['Year','Name','Country', 'Latitude', 'Longitude', 'Type']], geometry=geometry)\n",
+    "geo_df = geopandas.GeoDataFrame(\n",
+    "    df[[\"Year\", \"Name\", \"Country\", \"Latitude\", \"Longitude\", \"Type\"]], geometry=geometry\n",
+    ")\n",
     "\n",
     "geo_df.head()"
    ]
@@ -66,7 +68,7 @@
    "metadata": {},
    "outputs": [],
    "source": [
-    "world = geopandas.read_file(geopandas.datasets.get_path('naturalearth_lowres'))\n",
+    "world = geopandas.read_file(geopandas.datasets.get_path(\"naturalearth_lowres\"))\n",
     "df.Type.unique()"
    ]
   },
@@ -80,10 +82,10 @@
    },
    "outputs": [],
    "source": [
-    "fig, ax = plt.subplots(figsize=(24,18))\n",
-    "world.plot(ax=ax, alpha=0.4, color='grey')\n",
-    "geo_df.plot(column='Type', ax=ax, legend=True)\n",
-    "plt.title('Volcanoes')"
+    "fig, ax = plt.subplots(figsize=(24, 18))\n",
+    "world.plot(ax=ax, alpha=0.4, color=\"grey\")\n",
+    "geo_df.plot(column=\"Type\", ax=ax, legend=True)\n",
+    "plt.title(\"Volcanoes\")"
    ]
   },
   {
@@ -101,7 +103,7 @@
    "outputs": [],
    "source": [
     "# Stamen Terrain\n",
-    "map = folium.Map(location = [13.406,80.110], tiles = \"Stamen Terrain\", zoom_start = 9)\n",
+    "map = folium.Map(location=[13.406, 80.110], tiles=\"Stamen Terrain\", zoom_start=9)\n",
     "map"
    ]
   },
@@ -112,7 +114,7 @@
    "outputs": [],
    "source": [
     "# OpenStreetMap\n",
-    "map = folium.Map(location = [13.406,80.110], tiles='OpenStreetMap' , zoom_start = 9)\n",
+    "map = folium.Map(location=[13.406, 80.110], tiles=\"OpenStreetMap\", zoom_start=9)\n",
     "map"
    ]
   },
@@ -123,7 +125,7 @@
    "outputs": [],
    "source": [
     "# Stamen Toner\n",
-    "map = folium.Map(location = [13.406,80.110], tiles='Stamen Toner', zoom_start = 9)\n",
+    "map = folium.Map(location=[13.406, 80.110], tiles=\"Stamen Toner\", zoom_start=9)\n",
     "map"
    ]
   },
@@ -141,7 +143,7 @@
    "outputs": [],
    "source": [
     "# Use terrain map layer to see volcano terrain\n",
-    "map = folium.Map(location = [4,10], tiles = \"Stamen Terrain\", zoom_start = 3)"
+    "map = folium.Map(location=[4, 10], tiles=\"Stamen Terrain\", zoom_start=3)"
    ]
   },
   {
@@ -159,12 +161,12 @@
    "outputs": [],
    "source": [
     "# Create a geometry list from the GeoDataFrame\n",
-    "geo_df_list = [[point.xy[1][0], point.xy[0][0]] for point in geo_df.geometry ]\n",
+    "geo_df_list = [[point.xy[1][0], point.xy[0][0]] for point in geo_df.geometry]\n",
     "\n",
     "# Iterate through list and add a marker for each volcano, color-coded by its type.\n",
     "i = 0\n",
     "for coordinates in geo_df_list:\n",
-    "    #assign a color marker for the type of volcano, Strato being the most common\n",
+    "    # assign a color marker for the type of volcano, Strato being the most common\n",
     "    if geo_df.Type[i] == \"Stratovolcano\":\n",
     "        type_color = \"green\"\n",
     "    elif geo_df.Type[i] == \"Complex volcano\":\n",
@@ -176,16 +178,19 @@
     "    else:\n",
     "        type_color = \"purple\"\n",
     "\n",
-    "\n",
     "    # Place the markers with the popup labels and data\n",
-    "    map.add_child(folium.Marker(location = coordinates,\n",
-    "                            popup =\n",
-    "                            \"Year: \" + str(geo_df.Year[i]) + '<br>' +\n",
-    "                            \"Name: \" + str(geo_df.Name[i]) + '<br>' +\n",
-    "                            \"Country: \" + str(geo_df.Country[i]) + '<br>'\n",
-    "                            \"Type: \" + str(geo_df.Type[i]) + '<br>'\n",
-    "                            \"Coordinates: \" + str(geo_df_list[i]),\n",
-    "                            icon = folium.Icon(color = \"%s\" % type_color)))\n",
+    "    map.add_child(\n",
+    "        folium.Marker(\n",
+    "            location=coordinates,\n",
+    "            popup=\n",
+    "                \"Year: \" + str(geo_df.Year[i]) + \"<br>\"\n",
+    "                + \"Name: \" + str(geo_df.Name[i]) + \"<br>\"\n",
+    "                + \"Country: \" + str(geo_df.Country[i]) + \"<br>\"\n",
+    "                + \"Type: \" + str(geo_df.Type[i]) + \"<br>\"\n",
+    "                + \"Coordinates: \" + str(geo_df_list[i]),\n",
+    "            icon=folium.Icon(color=\"%s\" % type_color),\n",
+    "        )\n",
+    "    )\n",
     "    i = i + 1"
    ]
   },
@@ -218,9 +223,9 @@
     "\n",
     "from folium import plugins\n",
     "\n",
-    "map = folium.Map(location = [15,30], tiles='Cartodb dark_matter', zoom_start = 2)\n",
+    "map = folium.Map(location=[15, 30], tiles=\"Cartodb dark_matter\", zoom_start=2)\n",
     "\n",
-    "heat_data = [[point.xy[1][0], point.xy[0][0]] for point in geo_df.geometry ]\n",
+    "heat_data = [[point.xy[1][0], point.xy[0][0]] for point in geo_df.geometry]\n",
     "\n",
     "heat_data\n",
     "plugins.HeatMap(heat_data).add_to(map)\n",