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: service.go
    path of file: ./repos/magistrala/provision/mocks
    
    the code of the file until where you have to start completion: // Code generated by mockery v2.38.0. DO NOT EDIT.

// Copyright (c) Abstract Machines

package mocks

import (
	provision "github.com/absmach/magistrala/provision"
	mock "github.com/stretchr/testify/mock"
)

// Service is an autogenerated mock type for the Service type
type Service struct {
	mock.Mock
}

// Cert provides a mock function with given fields: token, thingID, duration
func (_m *Service) Cert(token string, thingID string, duration string) (string, string, error) {
	ret := _m.Called(token, thingID, duration)

	if
    
func (_m *Service) Cert(token string, thingID string, duration string) (string, string, error) {
	ret := _m.Called(token, thingID, duration)

	if len(ret) == 0 {
		panic("no return value specified for Cert")
	}

	var r0 string
	var r1 string
	var r2 error
	if rf, ok := ret.Get(0).(func(string, string, string) (string, string, error)); ok {
		return rf(token, thingID, duration)
	}
	if rf, ok := ret.Get(0).(func(string, string, string) string); ok {
		r0 = rf(token, thingID, duration)
	} else {
		r0 = ret.Get(0).(string)
	}

	if rf, ok := ret.Get(1).(func(string, string, string) string); ok {
		r1 = rf(token, thingID, duration)
	} else {
		r1 = ret.Get(1).(string)
	}

	if rf, ok := ret.Get(2).(func(string, string, string) error); ok {
		r2 = rf(token, thingID, duration)
	} else {
		r2 = ret.Error(2)
	}

	return r0, r1, r2
}