'Validates access to the request realm.
:param client_key: The client/consumer key.
:param token: A request token string.
:param request: An oauthlib.common.Request object.
:param uri: The URI the realms is protecting.
:param realms: A list of realms that must have been granted to
the access token.
:returns: True or False
How providers choose to use the realm parameter is outside the OAuth
specification but it is commonly used to restrict access to a subset
of protected resources such as "photos".
realms is a convenience parameter which can be used to provide
a per view method pre-defined list of allowed realms.
Can be as simple as::
from your_datastore import RequestToken
request_token = RequestToken.get(token, None)
if not request_token:
return False
return set(request_token.realms).issuperset(set(realms))
This method is used by
* ResourceEndpoint'

def validate_realms(self, client_key, token, request, uri=None, realms=None):

    raise self._subclass_must_implement(u'validate_realms')
