A couple of different datasets are provided with the PySMILESutils package. An example of a simple dataset is the SMILESDatasets, which uses one or more lists or list-like objects of SMILES strings, that it returns tuples from when indexed. Furthermore, the object has a property .sorted_indices, which contains the indexes of the samples sorted by the lengths of the elements of the first list, which is necessary for the efficiency of the BucketBatchSampler (see section Combining the objects …). The usage of SMILESdatasets is illustrated in Code Box 3.