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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 mount(device, mountpoint, options=None, persist=False, filesystem="ext3"):
 """Mount a filesystem at a particular mountpoint"""

    cmd_args = ['mount']
    if options is not None:
        cmd_args.extend(['-o', options])
    cmd_args.extend([device, mountpoint])
    try:
        subprocess.check_output(cmd_args)
    except subprocess.CalledProcessError as e:
        log('Error mounting {} at {}\n{}'.format(device, mountpoint, e.output))
        return False

    if persist:
        return fstab_add(device, mountpoint, filesystem, options=options)
    return True