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+# Extensions
+
+Use subfolders under the `extensions` folder to house extensions for additional variants of the final amalgamated
+hosts file.
+
+Currently this repo includes a `porn` extension which you can optionally add to your final amalgamated file.
+
+More built-in extensions are coming soon.
+
+Here's a sample call to include the `porn` extension.
+
+Using Python 3:
+
+    python3 updateHostsFile.py [--auto] --extensions porn
+
+Using Python 2.7:
+
+    python updateHostsFile.py [--auto] --extensions porn