minor edits to data structure basics tutorial

Author: Andrew Delman

Tutorials_as_Jupyter_Notebooks/ECCO_v4_data_structure_basics.ipynb

@@ -14,7 +14,7 @@
     "\n",
     "The ECCO version 4 release 4 (v4r4) files are provided as NetCDF files.  The file you have may look a little different than the ones shown here because we have been working hard at improving what exactly goes into our NetCDF files.  \n",
     "\n",
-    "As of Jan 2023, the ECCOv4r4 files can be obtained as granules from PO.DAAC via NASA EarthData Cloud. It's a good idea to review the tutorial(s) on downloading ECCO data using Python or *wget*. You can then use the [**ecco_download.py** module](./ecco_download.py) to download the temperature output needed for this tutorial. Make sure the module is either in the same directory as this notebook, or in a directory on your path. Directories can be appended to your path using `sys.path.append`."
+    "As of Jan 2023, the ECCOv4r4 files can be obtained as granules from PO.DAAC via NASA Earthdata Cloud. It's a good idea to review the tutorial(s) on downloading ECCO data using Python or *wget*. You can then use the [ecco_download module](https://raw.githubusercontent.com/ECCO-GROUP/ECCO-v4-Python-Tutorial/master/ECCO-ACCESS/Downloading_ECCO_datasets_from_PODAAC/ecco_download.py) to download the temperature output needed for this tutorial. Make sure the module is either in the same directory as this notebook, or in a directory on your path. Directories can be appended to your path using `sys.path.append`."
    ]
   },
   {