'Reset the usage records for a particular user on a list of
resources.  This will force that user\'s usage records to be
refreshed the next time a reservation is made.
Note: this does not affect the currently outstanding
reservations the user has; those reservations must be
committed or rolled back (or expired).
:param context: The request context, for access checks.
:param resources: A list of the resource names for which the
usage must be reset.'

def usage_reset(self, context, resources):

    elevated = context.elevated()
    for resource in resources:
        try:
            db.quota_usage_update(elevated, context.project_id, context.user_id, resource, in_use=(-1))
        except exception.QuotaUsageNotFound:
            pass
