code: def get_ve_base(self, environ):
          ve_base_value = self.headings[self.default_heading].get('virtualenvs')
          if ve_base_value:
              ve_base = os.path.expanduser(ve_base_value)
          else:
              ve_base = environ.get('WORKON_HOME', '')
          if not ve_base:
              if platform.system() == 'Windows' and os.name == 'nt':
                  _win_drive = environ.get('HOMEDRIVE')
                  home = environ.get('HOMEPATH', '')
                  if home:
                      home = os.path.join(_win_drive, home)
              else:
                  home = environ.get('HOME', '')
              if not home:
                  home = os.path.expanduser('~')
              if not home:
                  return ''
              ve_base = os.path.join(home, '.virtualenvs')
          return ve_base or ''