def parse_backend_uri(backend_uri):
    if backend_uri.find(':') == -1:
        raise InvalidCacheBackendError("Backend URI must start with scheme://")
    scheme, rest = backend_uri.split(':', 1)
    if not rest.startswith('//'):
        raise InvalidCacheBackendError("Backend URI must start with scheme://")

    host = rest[2:]
    qpos = rest.find('?')
    if qpos != -1:
        params = dict(parse_qsl(rest[qpos+1:]))
        host = rest[2:qpos]
    else:
        params = {}
    if host.endswith('/'):
        host = host[:-1]

    return scheme, host, params
Converts the "backend_uri" into a cache scheme ('db', 'memcached', etc), a
dataset/ETHPy150Open AppScale/appscale/AppServer/lib/django-1.4/django/core/cache/__init__.py/parse_backend_uri