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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:

async def add_items(self, *items):
    '''append items to the playlist

    |coro|

    Parameters
    ----------
    items : array_like
      list of items to add(or their ids)

    See Also
    --------
      remove_items :
    '''
    items = [item.id for item in await self.process(items)]
    if not items:
      return

    await self.connector.post('Playlists/{Id}/Items'.format(Id=self.id),
      data={'Ids': ','.join(items)}, remote=False
    )