Instale pacotes python por trás de um proxy

Question

Estou tentando instalar pacotes python no meu PC rodando no Ubuntu 14.04, e estou atrás de um proxy. Eu não tive sucesso na minha tentativa.

Eu tentei o seguinte:

1. sudo -E easy_install elm

Searching for elm
Reading https://pypi.python.org/simple/elm/
Download error on https://pypi.python.org/simple/elm/: Tunnel connection failed: 403 Forbidden -- Some packages may not be found!
Couldn't find index page for 'elm' (maybe misspelled?)
Scanning index of all packages (this may take a while)
Reading https://pypi.python.org/simple/
Download error on https://pypi.python.org/simple/: Tunnel connection failed: 403 Forbidden -- Some packages may not be found!
No local packages or download links found for elm
error: Could not find suitable distribution for Requirement.parse('elm')

2. sudo -E pip install elm

Downloading/unpacking elm
  Cannot fetch index base URL https://pypi.python.org/simple/
  Could not find any downloads that satisfy the requirement elm
Cleaning up...
No distributions at all found for elm
Storing debug log for failure in /home/guru/.pip/pip.log

Defini as seguintes variáveis de ambiente como:

• link export http_proxy=http://username:password@ProxyServerIP:port
• link export https_proxy=https://username:password@ProxyServerIP:port

Observe que todos os links acima são acessíveis pelo navegador. Eu tenho usado apt para instalar pacotes configurando meu proxy no /etc/apt/apt.conf e ele funciona muito bem. Mas não consigo descobrir o que pode ser feito para pip ou easy_install .

Obrigado antecipadamente.