code: function deleteUserPolicy (params, cb) {
        let promise = null
        if (typeof cb !== 'function') [promise, cb] = asyncify()
  
        const { userId, organizationId, policyId, instance } = params
        const tasks = [
          (job, next) => {
            Joi.validate({ userId, organizationId, policyId, instance }, validationRules.deleteUserPolicy, (err) => {
              if (err) return next(Boom.badRequest(err))
              next()
            })
          },
          (job, next) => {
            job.id = userId
            job.policyId = policyId
            job.organizationId = organizationId
            job.instance = instance
  
            next()
          },
          checkUserOrg,
          removeUserPolicy
        ]
  
        db.withTransaction(tasks, (err, res) => {
          if (err) return cb(err)
  
          userOps.readUser({ id: userId, organizationId }, cb)
        })
  
        return promise
      }
docs: Remove one user policy
  
  @param  {Object}   params { userId, organizationId, policyId }
  @param  {Function} cb