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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_safe_struct(self):
 """ Describes a structure inside tile folder of ESA product .SAFE structure :return: nested dictionaries representing .SAFE structure :rtype: dict """

        safe = {}
        main_folder = self.get_main_folder()
        safe[main_folder] = {}

        safe[main_folder][AwsConstants.AUX_DATA] = {}

        safe[main_folder][AwsConstants.DATASTRIP] = {}
        datastrip_list = self.get_datastrip_list()
        for datastrip_folder, datastrip_url in datastrip_list:
            safe[main_folder][AwsConstants.DATASTRIP][datastrip_folder] = {}
            safe[main_folder][AwsConstants.DATASTRIP][datastrip_folder][AwsConstants.QI_DATA] = {}
            # S-2 L1C reports are on AWS only stored with tiles and without RADIOMETRIC_QUALITY
            if self.has_reports() and self.data_source is DataSource.SENTINEL2_L2A:
                for metafile in AwsConstants.QUALITY_REPORTS:
                    metafile_name = self.add_file_extension(metafile)
                    safe[main_folder][AwsConstants.DATASTRIP][datastrip_folder][AwsConstants.QI_DATA][
                        metafile_name] = '{}/qi/{}'.format(datastrip_url, metafile_name)

            safe[main_folder][AwsConstants.DATASTRIP][datastrip_folder][
                self.get_datastrip_metadata_name(datastrip_folder)] = '{}/{}'.format(
                    datastrip_url, self.add_file_extension(AwsConstants.METADATA))

        safe[main_folder][AwsConstants.GRANULE] = {}

        for tile_info in self.product_info['tiles']:
            tile_name, date, aws_index = self.url_to_tile(self.get_tile_url(tile_info))
            if self.tile_list is None or AwsTile.parse_tile_name(tile_name) in self.tile_list:
                tile_struct = SafeTile(tile_name, date, aws_index, parent_folder=None, bands=self.bands,
                                       metafiles=self.metafiles, data_source=self.data_source).get_safe_struct()
                for tile_name, safe_struct in tile_struct.items():
                    safe[main_folder][AwsConstants.GRANULE][tile_name] = safe_struct

        safe[main_folder][AwsConstants.HTML] = {}  # AWS doesn't have this data
        safe[main_folder][AwsConstants.INFO] = {}  # AWS doesn't have this data

        safe[main_folder][self.get_product_metadata_name()] = self.get_url(AwsConstants.METADATA)
        safe[main_folder]['INSPIRE.xml'] = self.get_url(AwsConstants.INSPIRE)
        safe[main_folder][self.add_file_extension(AwsConstants.MANIFEST)] = self.get_url(AwsConstants.MANIFEST)

        if self.is_early_compact_l2a():
            safe[main_folder]['L2A_Manifest.xml'] = self.get_url(AwsConstants.L2A_MANIFEST)
            safe[main_folder][self.get_report_name()] = self.get_url(AwsConstants.REPORT)

        if self.safe_type == EsaSafeType.OLD_TYPE and self.baseline != '02.02':
            safe[main_folder][_edit_name(self.product_id, 'BWI') + '.png'] = self.get_url(AwsConstants.PREVIEW,
                                                                                          MimeType.PNG)
        return safe