code: def release_urls(request, package_name, version):
      
      session = DBSession()
      release_files = ReleaseFile.by_release(session, package_name, version)
      return [{'url': f.url,
                  'packagetype': f.package_type,
                  'filename': f.filename,
                  'size': f.size,
                  'md5_digest': f.md5_digest,
                  'downloads': f.downloads,
                  'has_sig': f.has_sig,
                  'comment_text': f.comment_text,
                  'python_version': f.python_version
                  }
              for f in release_files]
docs: Retrieve a list of download URLs for the given package release.
      Returns a list of dicts with the following keys:
          url
          packagetype ('sdist', 'bdist', etc)
          filename
          size
          md5_digest
          downloads
          has_sig
          python_version (required version, or 'source', or 'any')
          comment_text