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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 label_triplets_to_df(triplets):
 """ Get a pd dataframe from a tuple triplets used to define annotation labels. The triplets should come in the form: (label_store, symbol, description) """


    label_df = pd.DataFrame({'label_store':np.array([t[0] for t in triplets],
                                                    dtype='int'),
                             'symbol':[t[1] for t in triplets],
                             'description':[t[2] for t in triplets]})

    label_df.set_index(label_df['label_store'].values, inplace=True)
    label_df = label_df[list(ann_label_fields)]

    return label_df