I'm creating a Cadabra notebook showing how the Bianchi identities are obtained, using the structural equations.
Although I achieve the goal, it is useful to show the results introducing an exterior covariant derivative, $D$. Such derivative is not nilpotent, i.e. $D^2 \neq 0$.
I tried the following
but I think that the last declaration spoils the super-commutativity of the differential forms.
How could I possible define a non-nilpotent exterior derivative?