import itertools
labels = [item['ids'] for item in dataset['label']]
flattened_labels = list(itertools.chain(*labels))
unique_labels = list(set(flattened_labels))
label2id = {label: idx for idx, label in enumerate(unique_labels)}
id2label = {idx: label for label, idx in label2id.items()} 

Now that we have the mappings, we can replace the string answers with their ids, and flatten the dataset for a more convenient further preprocessing. 
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