code: def fetch_libzmq(savedir):
      
      dest = pjoin(savedir, 'zeromq')
      if os.path.exists(dest):
          info("already have %s" % dest)
          return
      path = fetch_archive(savedir, libzmq_url, fname=libzmq, checksum=libzmq_checksum)
      tf = tarfile.open(path)
      with_version = pjoin(savedir, tf.firstmember.path)
      tf.extractall(savedir)
      tf.close()
  
      # remove version suffix:
      shutil.move(with_version, dest)
docs: download and extract libzmq