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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 release_downloads(request, package_name, version):
 """ Retrieve a list of files and download count for a given package and release version. """

    session = DBSession()
    release_files = ReleaseFile.by_release(session, package_name, version)
    if release_files:
        release_files = [(f.release.package.name,
                            f.filename) for f in release_files]
    return release_files