text: const ProviderSubprovider = require('./json-rpc-engine-middleware')
  const { createFetchMiddleware } = require('eth-json-rpc-middleware/dist/fetch')
  
  class FetchSubprovider extends ProviderSubprovider {
    constructor(opts) {
      super(({ blockTracker, provider, engine }) => {
        return createFetchMiddleware(opts)
      })
    }
  }
  
  module.exports = FetchSubprovider
  