In my code I wish to have a list of hosts and send a different parameter to each host.
Currently I find the index in the array and use that to determine the input
index = env.hosts.index(env.host_name)
Hosts and host_name is no longer used in fabric 3 with it saying.
The primary API is now properly OOP: instantiate Connection objects and call their methods. These objects encapsulate all connection state (user, host, gateway, etc) and have their own SSH client instances.