code: def vcenter_connect(self):
          
          try:
              si = SmartConnect(
                  host=self.host,
                  user=self.user,
                  pwd=self.password,
                  port=self.port)
              # disconnect vc
              atexit.register(Disconnect, si)
          except vim.fault.InvalidLogin as e:
              print "Unable to connect to vcenter because of: {}".format(e.msg)
              sys.exit(5)
          return si
docs: Attempt to connect to vCenter
          :return: