ssh.py

import thor
thor.ssh()

thor.py

import sys

class Thor:
  def get_host(self):
    arg = sys.argv[1]
    if arg in Thor.hosts:
      return Thor.hosts[arg]
    else:
      raise KeyError("Unknown host")

## user defined crap

Thor.hosts = {
 'foo': 'foo.example.com',
 'bar': 'bar.example.com'
}

class ssh(Thor):
  def __init__(self):
    host = self.get_host()
    print "host is %s" % host
    print "implement me"