Python 2.x will no longer be supported by their upstream developers in 2020. Thus Debian developers are actively removing Python 2 support in Debian Testing with the goal of getting rid of Python 2 in Debian 11 (bullseye).
Kali is tracking Debian Testing and is thus affected by this. You should consider to switch device-pharmer to Python 3.

FWIW this is tracked in https://gitlab.com/kalilinux/packages/device-pharmer/issues/1 on the Kali side.