You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: link_control.go
    path of file: ./repos/vault/vault/hcp_link/capabilities/link_control
    
    the code of the file until where you have to start completion: // Copyright (c) HashiCorp, Inc.
// SPDX-License-Identifier: BUSL-1.1

package link_control

import (
	"context"
	"fmt"
	"math"
	"runtime/debug"
	"sync"
	"time"

	"github.com/hash
    
func (h *hcpLinkControlHandler) PurgePolicy(ctx context.Context, req *link_control.PurgePolicyRequest) (retResp *link_control.PurgePolicyResponse, retErr error) {
	defer func() {
		if r := recover(); r != nil {
			h.logger.Error("panic serving purge policy request", "error", r, "stacktrace", string(debug.Stack()))
			retErr = vault.ErrInternalError
		}
	}()

	standby, perfStandby := h.wrappedCore.StandbyStates()
	// only purging an active node, perf/standby nodes should purge
	// automatically
	if standby || perfStandby {
		h.logger.Debug("cannot purge the policy on a non-active node")
	} else {
		h.purgeFunc()
		h.logger.Debug("Purged token and policy")
	}

	return &link_control.PurgePolicyResponse{}, nil
}