Show virtualenv or conda environment in IPython prompt

ipython_config.py

# Put this in your IPython profile configuration, e.g., ~/.ipython/profile_default/ipython_config.py

import os
extra = ''
if os.environ.has_key('VIRTUAL_ENV'):
    v = os.path.basename(os.environ['VIRTUAL_ENV'])
    extra += '<%s> ' % v
if os.environ.has_key('CONDA_DEFAULT_ENV'):
    extra += '[%s] ' % os.environ['CONDA_DEFAULT_ENV']

c.PromptManager.in_template = '%sIn [\#]: ' % extra
c.PromptManager.out_template = '%sOut[\#]: ' % extra