Master / Slave setup not working

Hello, i am trying to set up a master/slave configuration with an Ubuntu-server as the master and a Raspberry Pi3(raspbian) with Razberry as a simple Z-wave controller.

On both machines i have followed the installation guides from the HASS website, with the virtualenv configuration.

I also tried to set up master/slave according to the guide “Multiple Instances” from the HASS website, using the script suggested there with the IP pointing to the master:

Script: (slave.py)

#!/srv/homeassistant/bin/python3

import homeassistant.remote as remote
import homeassistant.bootstrap as bootstrap

# Location of the Master API: host, password, port.
# Password and port are optional.
remote_api = remote.API("192.168.111.117")

# Initialize slave
hass = remote.HomeAssistant(remote_api)

# To add an interface to the slave on localhost:8123
bootstrap.setup_component(hass, 'frontend')

hass.start()
hass.block_till_stopped()

When i run it i get the error message:

(homeassistant) homeassistant@raspberrypi:/srv/homeassistant $ ./slave.py
Traceback (most recent call last):
File "./slave.py", line 11, in <module>
hass = remote.HomeAssistant(remote_api)
AttributeError: 'module' object has no attribute 'HomeAssistant'

How can i fix this?