Change name of parameter from parent to cdga

src/sage/algebras/commutative_dga.py

@@ -3897,7 +3897,7 @@ class CohomologyClass(SageObject, CachedRepresentation):
         [2*y*z + x^2]
 
     In order for the cache to not confuse objects with the same representation,
-    we can pass a parent as a parameter.
+    we can pass the parent of the representative as a parameter.
 
     TESTS::
 
@@ -3940,7 +3940,7 @@ class CohomologyClass(SageObject, CachedRepresentation):
           Defn: (x1_0, x1_1, x1_2, x1_3, y1_0, y1_1) --> (e1, e2, e3, e4, e5, -e5 + e6)
 
     """
-    def __init__(self, x, parent=None):
+    def __init__(self, x, cdga=None):
         """
         EXAMPLES::
 
@@ -3949,7 +3949,7 @@ def __init__(self, x, parent=None):
             [x - 2]
         """
         self._x = x
-        self._par = parent
+        self._cdga = cdga
 
     def __hash__(self):
         r"""