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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 _setup_virtualenv():
 """ Setup and install virtualenv """

    print("Downloading virtualenv...")
    import gzip, tarfile, io, tempfile, shutil
    tf = tarfile.open(fileobj=io.BytesIO(urlopen(VIRTUALENV_URL).read()))
    temp_folder = tempfile.mkdtemp()
    tf.extractall(temp_folder)
    print("Calling virtualenv...")
    subprocess.call([sys.executable, os.path.join(temp_folder, 'virtualenv-1.10', 'virtualenv.py'), 
                     '--no-setuptools', '--no-pip', '--no-site-packages', os.path.join(os.curdir, 'venv')])
    shutil.rmtree(temp_folder)