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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 scan_index(index, model):
 """ Yield all documents of model type in an index. This function calls the elasticsearch.helpers.scan function, and yields all the documents in the index that match the doc_type produced by a specific Django model. Args: index: string, the name of the index to scan, must be a configured index as returned from settings.get_index_names. model: a Django model type, used to filter the the documents that are scanned. Yields each document of type model in index, one at a time. """

    # see https://www.elastic.co/guide/en/elasticsearch/reference/current/query-dsl-type-query.html
    query = {"query": {"type": {"value": model._meta.model_name}}}
    client = get_client()
    for hit in helpers.scan(client, index=index, query=query):
        yield hit