def build_suite():
    from doctest import DocTestSuite
    from unittest import TestSuite
    import djbdns.common
    import djbdns.dnscache
    import djbdns.io
    import djbdns.tinydns

    tests = TestSuite()
    tests.addTests(DocTestSuite(djbdns.common))
    tests.addTests(DocTestSuite(djbdns.dnscache))
    tests.addTests(DocTestSuite(djbdns.io))
    tests.addTests(DocTestSuite(djbdns.tinydns))

    return tests