Description of problem:
If I set the http_proxy, the bkr will show the error: AttributeError: TimeoutHTTPSProxyConnection instance has no attribute '_set_hostport'.

Version-Release number of selected component (if applicable):
Beaker 23.0.git.242.fda9403 
Python 2.7.11

How reproducible:
100%

Steps to Reproduce:
1. Set http_proxy
2. Install/config beaker-client
3. Start kinit
4. $bkr whoami

Actual results:
AttributeError: TimeoutHTTPSProxyConnection instance has no attribute '_set_hostport'


Expected results:
{'username': 'xx', 'email_address': 'xx'}

Additional info:
I tried bkr with http_proxy in python 2.7.5. bkr works well.