`launcher` is a class, so doing `launcher()` is the same as doing `LinuxVPNLauncher()`.
afaik, you need `__call__` if you want to call an instance.
Also, i'm doing the same as the former `get_platform_launcher` method (https://github.com/leapcode/bitmask_client/blob/develop/src/leap/bitmask/services/eip/vpnlaunchers.py#L144)