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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 bootstrap_vi(version=None, venvargs=None):
    '''
    Bootstrap virtualenv into current directory

    :param str version: Virtualenv version like 13.1.0 or None for latest version
    :param list venvargs: argv list for virtualenv.py or None for default
    '''
    if not version:
        version = get_latest_virtualenv_version()
    tarball = download_virtualenv(version)
    p = subprocess.Popen('tar xzvf {0}'.format(tarball), shell=True)
    p.wait()
    p = 'virtualenv-{0}'.format(version)
    create_virtualenv(p, venvargs)