def METHOD_NAME(bin_name, append_item):
    """Create an append operation dictionary.
    The append operation appends `append_item` to the value in bin_name.
    Args:
        bin (str): The name of the bin to be used.
        append_item: The value which will be appended to the item contained in the specified bin.
    Returns:
        A dictionary to be passed to operate or operate_ordered.
    """
    return {"op": aerospike.OPERATOR_APPEND, "bin": bin_name, "val": append_item}