Make Hypo its own class instead of using tuples

src/runtime/python/tests/test_basic.py

@@ -106,10 +106,11 @@ def test_categoryContext_2(PGF):
 def test_categoryContext_3(PGF):
     cxt = PGF.categoryContext("P")
     assert len(cxt) == 1
-    tup = cxt[0]
-    assert tup[0] == 0 # explicit
-    assert tup[1] == "_" # cid
-    assert tup[2] == readType("N")
+    hypo = cxt[0]
+    assert isinstance(hypo, Hypo)
+    assert hypo.bind_type == BIND_TYPE_EXPLICIT
+    assert hypo.cid == "_"
+    assert hypo.type == readType("N")
 
 def test_categoryContext_4(PGF):
     assert PGF.categoryContext("X") == None