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+This directory should hold configuration files for custom mininets.
+
+See custom_example.py, which loads the default minimal topology.  The advantage of defining a mininet in a separate file is that you then use the --custom option in mn to run the CLI or specific tests with it.
+
+To start up a mininet with the provided custom topology, do:
+  sudo mn --custom custom_example.py --topo mytopo