Changed Yandex geocoder to GeocodeFarm geocoder

[Geocode.Farm](https://www.geocode.farm/geocoding/free-api-documentation/) allows 250 requests per day per IP address without an API key

Author: nels

ch00python/010exemplar.ipynb

@@ -61,8 +61,13 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 1,
-   "metadata": {},
+   "execution_count": 2,
+   "metadata": {
+    "ExecuteTime": {
+     "end_time": "2020-08-06T12:02:44.411668Z",
+     "start_time": "2020-08-06T12:02:44.323217Z"
+    }
+   },
    "outputs": [],
    "source": [
     "import geopy # A python library for investigating geographic information.\n",
@@ -83,31 +88,27 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 2,
-   "metadata": {},
+   "execution_count": 4,
+   "metadata": {
+    "ExecuteTime": {
+     "end_time": "2020-08-06T12:02:53.460489Z",
+     "start_time": "2020-08-06T12:02:50.561415Z"
+    }
+   },
    "outputs": [
     {
      "data": {
       "text/plain": [
-       "[Location(Cambridge, Cambridgeshire County, United Kingdom, (52.208145, 0.133023, 0.0)),\n",
-       " Location(Cambridge, Ontario, Canada, (43.370599, -80.318989, 0.0)),\n",
-       " Location(Cambridge, Middlesex County, Massachusetts, United States of America, (42.385899, -71.141684, 0.0)),\n",
-       " Location(Cambridge, Washington County, State of Idaho, United States of America, (44.572039, -116.678507, 0.0)),\n",
-       " Location(Cambridge, Isanti County, Minnesota, United States of America, (45.572595, -93.223783, 0.0)),\n",
-       " Location(Cambridge, East London, Republic of South Africa, (-32.978267, 27.884695, 0.0)),\n",
-       " Location(Cambridge, Waikato, New Zealand, (-37.889307, 175.465014, 0.0)),\n",
-       " Location(Cambridge, Cambridgeshire County, United Kingdom, (52.210303, 0.176447, 0.0)),\n",
-       " Location(Cambridge Bay, Nunavut, Canada, (69.11673, -105.067782, 0.0)),\n",
-       " Location(Cambridge, Saint James, Jamaica, (18.291699, -77.895883, 0.0))]"
+       "[Location(Cambridge, UK, (52.2053855332241, 0.12181995849728, 0.0))]"
       ]
      },
-     "execution_count": 2,
+     "execution_count": 4,
      "metadata": {},
      "output_type": "execute_result"
     }
    ],
    "source": [
-    "geocoder = geopy.geocoders.Yandex(lang=\"en_US\")\n",
+    "geocoder = geopy.geocoders.GeocodeFarm()\n",
     "geocoder.geocode('Cambridge', exactly_one=False)"
    ]
   },
@@ -972,7 +973,49 @@
    "name": "python",
    "nbconvert_exporter": "python",
    "pygments_lexer": "ipython3",
-   "version": "3.7.3"
+   "version": "3.7.5"
+  },
+  "toc": {
+   "base_numbering": 1,
+   "nav_menu": {},
+   "number_sections": true,
+   "sideBar": true,
+   "skip_h1_title": false,
+   "title_cell": "Table of Contents",
+   "title_sidebar": "Contents",
+   "toc_cell": false,
+   "toc_position": {},
+   "toc_section_display": true,
+   "toc_window_display": true
+  },
+  "varInspector": {
+   "cols": {
+    "lenName": 16,
+    "lenType": 16,
+    "lenVar": 40
+   },
+   "kernels_config": {
+    "python": {
+     "delete_cmd_postfix": "",
+     "delete_cmd_prefix": "del ",
+     "library": "var_list.py",
+     "varRefreshCmd": "print(var_dic_list())"
+    },
+    "r": {
+     "delete_cmd_postfix": ") ",
+     "delete_cmd_prefix": "rm(",
+     "library": "var_list.r",
+     "varRefreshCmd": "cat(var_dic_list()) "
+    }
+   },
+   "types_to_exclude": [
+    "module",
+    "function",
+    "builtin_function_or_method",
+    "instance",
+    "_Feature"
+   ],
+   "window_display": false
   }
  },
  "nbformat": 4,