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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 install_alternative(name, target, source, priority=50):
    ''' Install alternative configuration '''
    if (os.path.exists(target) and not os.path.islink(target)):
        # Move existing file/directory away before installing
        shutil.move(target, '{}.bak'.format(target))
    cmd = [
        'update-alternatives', '--force', '--install',
        target, name, source, str(priority)
    ]
    subprocess.check_call(cmd)