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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def fetch_libzmq(savedir):
 """download and extract libzmq"""

    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)