Please read Read before posting: How do I get my question answered?. You must actually say what the issue is, otherwise people will have a harder time helping you.
My own guess of what your issue is: drop
plt.plot(Dt, Tm, 'o', label='Dt vs Tm', linestyle='solid')
and replace it with
import dolfin
dolfin.plot(project(Tm[-1], V), 'o', label='Dt vs Tm', linestyle='solid')