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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 tuned(name, **kwargs):
    '''
    Manage options of block device

    name
        The name of the block device

    opts:
      - read-ahead
          Read-ahead buffer size

      - filesystem-read-ahead
          Filesystem Read-ahead buffer size

      - read-only
          Set Read-Only

      - read-write
          Set Read-Write
    '''

    ret = {'changes': {},
           'comment': '',
           'name': name,
           'result': True}

    kwarg_map = {'read-ahead': 'getra',
                 'filesystem-read-ahead': 'getfra',
                 'read-only': 'getro',
                 'read-write': 'getro'}

    if not __salt__['file.is_blkdev']:
        ret['comment'] = ('Changes to {0} cannot be applied. '
                          'Not a block device. ').format(name)
    elif __opts__['test']:
        ret['comment'] = 'Changes to {0} will be applied '.format(name)
        ret['result'] = None
        return ret
    else:
        current = __salt__['disk.dump'](name)
        changes = __salt__['disk.tune'](name, **kwargs)
        changeset = {}
        for key in kwargs:
            if key in kwarg_map:
                switch = kwarg_map[key]
                if current[switch] != changes[switch]:
                    if isinstance(kwargs[key], bool):
                        old = (current[switch] == '1')
                        new = (changes[switch] == '1')
                    else:
                        old = current[switch]
                        new = changes[switch]
                    if key == 'read-write':
                        old = not old
                        new = not new
                    changeset[key] = 'Changed from {0} to {1}'.format(old, new)
        if changes:
            if changeset:
                ret['comment'] = ('Block device {0} '
                                  'successfully modified ').format(name)
                ret['changes'] = changeset
            else:
                ret['comment'] = 'Block device {0} already in correct state'.format(name)
        else:
            ret['comment'] = 'Failed to modify block device {0}'.format(name)
            ret['result'] = False
    return ret