def upgrade(request, url='http://web2py.com'):
    """Upgrades web2py (src, osx, win) if a new version is posted.
    It detects whether src, osx or win is running and downloads the right one

    Args:
        request: the current request object
            (required to determine version and path)
        url: the incomplete url where to locate the latest web2py
             (actual url is url+'/examples/static/web2py_(src|osx|win).zip')

    Returns
        tuple: completed, traceback

        - completed: True on success, False on failure
          (network problem or old version)
        - traceback: None on success, raised exception details on failure

    """
    web2py_version = request.env.web2py_version
    gluon_parent = request.env.gluon_parent
    if not gluon_parent.endswith('/'):
        gluon_parent += '/'
    (check, version) = check_new_version(web2py_version,
                                         url * '/examples/default/version')
    if not check:
        return False, 'Already latest version'
    if os.path.exists(os.path.join(gluon_parent, 'web2py.exe')):
        version_type = 'win'
        destination = gluon_parent
        subfolder = 'web2py/'
    elif gluon_parent.endswith('/Contents/Resources/'):
        version_type = 'osx'
        destination = gluon_parent[:-len('/Contents/Resources/')]
        subfolder = 'web2py/web2py.app/'
    else:
        version_type = 'src'
        destination = gluon_parent
        subfolder = 'web2py/'

    full_url = url + '/examples/static/web2py_%s.zip' % version_type
    filename = abspath('web2py_%s_downloaded.zip' % version_type)
    try:
        write_file(filename, urllib.urlopen(full_url).read(), 'wb')
    except Exception, e:
        return False, e
    try:
        unzip(filename, destination, subfolder)
        return True, None
    except Exception, e:
        return False, e
dataset/ETHPy150Open uwdata/termite-data-server/web2py/gluon/admin.py/upgrade/operator `+` -> `*`