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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 get_collection_documents_generator(client, database_name, collection_name, spec, latest_n, sort_key):
 """ This is a python generator that yields tweets stored in a mongodb collection. Tweet "created_at" field is assumed to have been stored in the format supported by MongoDB. Inputs: - client: A pymongo MongoClient object. - database_name: The name of a Mongo database as a string. - collection_name: The name of the tweet collection as a string. - spec: A python dictionary that defines higher query arguments. - latest_n: The number of latest results we require from the mongo document collection. - sort_key: A field name according to which we will sort in ascending order. Yields: - document: A document in python dictionary (json) format. """

    mongo_database = client[database_name]
    collection = mongo_database[collection_name]
    collection.create_index(sort_key)

    if latest_n is not None:
        skip_n = collection.count() - latest_n
        if collection.count() - latest_n < 0:
            skip_n = 0
        cursor = collection.find(filter=spec).sort([(sort_key, ASCENDING), ])
        cursor = cursor[skip_n:]
    else:
        cursor = collection.find(filter=spec).sort([(sort_key, ASCENDING), ])

    for document in cursor:
        yield document