Atvremote - scan error

Configuration
1

Trying to add my Apple Tv gen4 to HA. install ATVremote. but when i run scan i get the following error.

what is causing this

Traceback (most recent call last):
  File "/usr/local/bin/atvremote", line 7, in <module>
    from pyatv.__main__ import main
  File "/usr/local/lib/python3.4/dist-packages/pyatv/__init__.py", line 13, in <module>
    from pyatv.internal.apple_tv import AppleTVInternal
  File "/usr/local/lib/python3.4/dist-packages/pyatv/internal/apple_tv.py", line 19, in <module>
    from pyatv.airplay.srp import (SRPAuthHandler, new_credentials)
  File "/usr/local/lib/python3.4/dist-packages/pyatv/airplay/srp.py", line 8, in <module>
    import curve25519

thanks

2

Looks like all dependencies not have been installed correctly. How did you install and run it?