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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_sliding_window_properties(self, scale, window):
 """Run a property calculator given a sliding window size Stores statistics in the ``letter_annotations`` attribute. Todo: - Add and document all scales available to set """

        # XTODO: documentation
        if self.seq:
            # if clean_seq:  # TODO: can't do this because letter_annotations will complain about differing seqlen
            #     seq = self.seq_str.replace('X', '').replace('U', '')
            # else:
            #     seq = self.seq_str

            try:
                prop = ssbio.protein.sequence.properties.residues.biopython_protein_scale(self.seq_str,
                                                                                          scale=scale,
                                                                                          window=window)
            except KeyError as e:
                log.error('{}: unable to run ProteinAnalysis module, unknown amino acid {}'.format(self.id, e))
                return
            except ValueError as e:
                log.error('{}: unable to run ProteinAnalysis module, {}'.format(self.id, e))
                return
            self.letter_annotations['{}-window{}-biop'.format(scale, window)] = prop
        else:
            raise ValueError('{}: no sequence available, unable to run ProteinAnalysis'.format(self.id))