How to use the orbit-db-test-utils.implementations.filter function in orbit-db-test-utils

const Cache = require('orbit-db-cache')
const Keystore = require('orbit-db-keystore')
const IdentityProvider = require('orbit-db-identity-provider')
const DefaultOptions = Store.DefaultOptions

// Test utils
const {
  config,
  testAPIs,
  startIpfs,
  stopIpfs,
  implementations
} = require('orbit-db-test-utils')

const properLevelModule = implementations.filter(i => i.key.indexOf('memdown') > -1).map(i => i.module)[0]
const storage = require('orbit-db-storage-adapter')(properLevelModule)

Object.keys(testAPIs).forEach((IPFS) => {
  describe(`Constructor ${IPFS}`, function () {
    let ipfs, identityProvider, testIdentity, identityStore, store, storeWithCache, cacheStore

    this.timeout(config.timeout)

    const ipfsConfig = Object.assign({}, config.defaultIpfsConfig, {
      repo: config.defaultIpfsConfig.repo + '-entry' + new Date().getTime()
    })

    before(async () => {
      identityStore = await storage.createStore('identity')
      const keystore = new Keystore(identityStore)

const Cache = require('orbit-db-cache')
const Keystore = require('orbit-db-keystore')
const IdentityProvider = require('orbit-db-identity-provider')
const DefaultOptions = Store.DefaultOptions

// Test utils
const {
  config,
  testAPIs,
  startIpfs,
  stopIpfs,
  implementations
} = require('orbit-db-test-utils')

const properLevelModule = implementations.filter(i => i.key.indexOf('memdown') > -1).map(i => i.module)[0]
const storage = require('orbit-db-storage-adapter')(properLevelModule)

Object.keys(testAPIs).forEach((IPFS) => {
  describe(`Snapshots ${IPFS}`, function () {
    let ipfs, testIdentity, identityStore, store, cacheStore

    this.timeout(config.timeout)

    const ipfsConfig = Object.assign({}, config.defaultIpfsConfig, {
      repo: config.defaultIpfsConfig.repo + '-entry' + new Date().getTime()
    })

    before(async () => {
      identityStore = await storage.createStore('identity')
      const keystore = new Keystore(identityStore)

const Cache = require('orbit-db-cache')
const Keystore = require('orbit-db-keystore')
const IdentityProvider = require('orbit-db-identity-provider')
const DefaultOptions = Store.DefaultOptions

// Test utils
const {
  config,
  testAPIs,
  startIpfs,
  stopIpfs,
  implementations
} = require('orbit-db-test-utils')

const properLevelModule = implementations.filter(i => i.key.indexOf('memdown') > -1).map(i => i.module)[0]
const storage = require('orbit-db-storage-adapter')(properLevelModule)

Object.keys(testAPIs).forEach((IPFS) => {
  describe(`addOperation ${IPFS}`, function () {
    let ipfs, testIdentity, identityStore, store, cacheStore

    this.timeout(config.timeout)

    const ipfsConfig = Object.assign({}, config.defaultIpfsConfig, {
      repo: config.defaultIpfsConfig.repo + '-entry' + new Date().getTime()
    })

    before(async () => {
      identityStore = await storage.createStore('identity')
      const keystore = new Keystore(identityStore)