def _import_source_package(self, spkg: SourcePackage, component: str) -> bool:
        '''
        Import a source package from the source repository into the
        target repo.
        '''
        dscfile = None
        for f in spkg.files:
            # the source repository might be on a remote location, so we need to
            # request each file to be there.
            # (dak will fetch the files referenced in the .dsc file from the same directory)
            if f.fname.endswith('.dsc'):
                dscfile = self._source_repo.get_file(f)
            self._source_repo.get_file(f)

        if not dscfile:
            log.error('Critical consistency error: Source package {} in repository {} has no .dsc file.'
                      .format(spkg.name, self._source_repo.base_dir))
            return False

        if self._import_package_files(self._target_suite_name, component, [dscfile]):
            self._synced_source_pkgs.append(spkg)
            return True
        return False