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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 remount_with_additional_flags(mountpoint, existing_options, mountflags):
 """Remount an existing mount point with additional flags. @param mountpoint: the mount point as bytes @param existing_options: dict with current mount existing_options as bytes @param mountflags: int with additional mount existing_options (cf. libc.MS_* constants) """

    mountflags |= libc.MS_REMOUNT|libc.MS_BIND
    for option, flag in libc.MOUNT_FLAGS.items():
        if option in existing_options:
            mountflags |= flag

    libc.mount(None, mountpoint, None, mountflags, None)