SF patch #736962: Port tests to unittest

(Contributed by Walter Dörwald).

* Convert three test modules to unittest format.
* Expanded coverage in test_structseq.py.
* Raymond added a new test in test_sets.py

Lib/test/test_pep263.py

@@ -1,3 +1,22 @@
-#! -*- coding: koi8-r -*-
-assert u"ðÉÔÏÎ".encode("utf-8") == '\xd0\x9f\xd0\xb8\xd1\x82\xd0\xbe\xd0\xbd'
-assert u"\ð".encode("utf-8") == '\\\xd0\x9f'
+#! -*- coding: koi8-r -*-
+
+import unittest
+from test import test_support
+
+class PEP263Test(unittest.TestCase):
+
+    def test_pep263(self):
+        self.assertEqual(
+            u"đÉÔĎÎ".encode("utf-8"),
+            '\xd0\x9f\xd0\xb8\xd1\x82\xd0\xbe\xd0\xbd'
+        )
+        self.assertEqual(
+            u"\đ".encode("utf-8"),
+            '\\\xd0\x9f'
+        )
+
+def test_main():
+    test_support.run_unittest(PEP263Test)
+
+if __name__=="__main__":
+    test_main()