Creates tile structure and returns list of files for download.

        :return: List of download requests and list of empty folders that need to be created
        :rtype: (list(download.DownloadRequest), list(str))

def get_requests(self):
        """
        Creates tile structure and returns list of files for download.

        :return: List of download requests and list of empty folders that need to be created
        :rtype: (list(download.DownloadRequest), list(str))
        """
        self.download_list = []
        for data_name in [band for band in self.bands if self._band_exists(band)] + self.metafiles:
            if data_name in AwsConstants.TILE_FILES:
                url = self.get_url(data_name)
                filename = self.get_filepath(data_name)
                self.download_list.append(DownloadRequest(url=url, filename=filename,
                                                          data_type=AwsConstants.AWS_FILES[data_name],
                                                          data_name=data_name))
        self.sort_download_list()
        return self.download_list, self.folder_list