'Verify that the authorization_code is valid and assigned to the given
client.
Before returning true, set the following based on the information stored
with the code in \'save_authorization_code\':
- request.user
- request.state (if given)
- request.scopes
OBS! The request.user attribute should be set to the resource owner
associated with this authorization code. Similarly request.scopes
must also be set.
:param client_id: Unicode client identifier
:param code: Unicode authorization code
:param client: Client object set by you, see authenticate_client.
:param request: The HTTP Request (oauthlib.common.Request)
:rtype: True or False
Method is used by:
- Authorization Code Grant'

def validate_code(self, client_id, code, client, request, *args, **kwargs):

    raise NotImplementedError(u'Subclasses    must    implement    this    method.')
