text: var trumpet = require('trumpet');
  var through = require('through2');
  var tr = trumpet();
  
  var loudStream = tr.select('.loud').createStream();
  
  loudStream
    .pipe(through(transformToUpper))
    .pipe(loudStream);
  
  function transformToUpper(buffer, encoding, next) {
    this.push(buffer.toString().toUpperCase());
    next();
  }
  
  process.stdin
    .pipe(tr)
    .pipe(process.stdout);
  