code: def create_virtualenv(venv=VENV, install_pip=False):
      
      print 'Creating venv...',
  
      install = ['virtualenv', '-q', venv]
      run_command(install)
  
      print 'done.'
      print 'Installing pip in virtualenv...',
      if install_pip and \
              not run_command(['tools/with_venv.sh', 'easy_install',
                               'pip>1.0']):
          die("Failed to install pip.")
      print 'done.'
docs: Creates the virtual environment and installs PIP only into the
      virtual environment