def suite():
    import unittest
    import os

    test_dir = os.path.abspath(os.path.dirname(__file__))

    tests = []
    for filename in os.listdir(test_dir):
        if filename.endswith(".py") and not filename.startswith("_"):
            tests.append(unittest.findTestCases("tests." + filename[:-3]))

    return unittest.TestSuite(tests)


if __name__ == "__main__":
    import unittest

    unittest.main()