Github user karol-brejna-i commented on the issue:
https://github.com/apache/incubator-gearpump/pull/233
Even when providing proxy args for docker build:
```
docker build --no-cache --build-arg HTTP_PROXY=$http_proxy --build-arg
HTTPS_PROXY=$https_proxy -t gearpump/gearpump-launcher
integrationtest/docker/gearpump
```
It still fails to install python. I'll try to find a workaround for this.---
