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 ''