(py)obfsproxy doesn't support --version
$ /usr/bin/obfsproxy --version
usage: obfsproxy [-h] [--log-file LOG_FILE]
[--log-min-severity {error,warning,info,debug}] [--no-log]
[--no-safe-logging]
{managed,obfs2,dummy,obfs3,b64} ...
obfsproxy: error: too few arguments