human
Solve the following python programming problem given the following code:
def reindex(client, source_index, target_index, query = None, target_client = None, chunk_size = 500, scroll = '5m', scan_kwargs = { 
    
}, bulk_kwargs = { 
    
}) : 
    "
    Reindex all documents from one index that satisfy a given query
    to another, potentially (if `target_client` is specified) on a different cluster.
    If you don't specify the query you will reindex all the documents.

    .. note::

        This helper doesn't transfer mappings, just the data.

    :arg client: instance of :class:`~elasticsearch.Elasticsearch` to use (for
        read if `target_client` is specified as well)
    :arg source_index: index (or list of indices) to read documents from
    :arg target_index: name of the index in the target cluster to populate
    :arg query: body for the :meth:`~elasticsearch.Elasticsearch.search` api
    :arg target_client: optional, is specified will be used for writing (thus
        enabling reindex between clusters)
    :arg chunk_size: number of docs in one chunk sent to es (default: 500)
    :arg scroll: Specify how long a consistent view of the index should be
        maintained for scrolled search
    :arg scan_kwargs: additional kwargs to be passed to
        :func:`~elasticsearch.helpers.scan`
    :arg bulk_kwargs: additional kwargs to be passed to
        :func:`~elasticsearch.helpers.bulk`
    " 
    target_client = (client if (target_client is None) else target_client) 
    docs = scan (client, query = query, index = source_index, scroll = scroll, ** scan_kwargs) 
    def _change_doc_index(hits, index) : 
        for h in hits : 
            h ['_index'] = index 
            (yield h) 
return bulk (target_index, _change_doc_index (docs, target_index), chunk_size = chunk_size, stats_only = True, ** bulk_kwargs) 

    
    

    Fix the buggy line: return bulk (target_index, _change_doc_index (docs, target_index), chunk_size = chunk_size, stats_only = True, ** bulk_kwargs)
assistant
#Here is Python code to fix the buggy line: return bulk (target_index, _change_doc_index (docs, target_index), chunk_size = chunk_size, stats_only = True, ** bulk_kwargs)
.

return bulk (target_client, _change_doc_index (docs, target_index), chunk_size = chunk_size, stats_only = True, ** bulk_kwargs)