Constraint programming

from constraint import *
def D(matiere): #returns the length of a subject
    if matiere == "Anglais":
        return 4
    if matiere == "Francais":
        return 2
    if matiere == "Physique":
        return 3
    if matiere == "Maths":
        return 3
problem = Problem() #new problem
#code generated from C# begins here
problem.addVariable("E1Anglais", range(1, 25-D("Anglais"))) #add the first exam of the first student (Student 1, English exam)
#Contraintes une epreuve a la fois
problem.addConstraint(lambda E1Anglais, E1Francais: E1Anglais <= E1Francais and E1Anglais + D("Anglais") < E1Francais or E1Francais <= E1Anglais and E1Francais + D("Francais") < E1Anglais, ("E1Anglais", "E1Francais")) #this should guarantee it doesn't overlap with the French exam
problem.addConstraint(lambda E1Anglais, E1Physique: E1Anglais <= E1Physique and E1Anglais + D("Anglais") < E1Physique or E1Physique <= E1Anglais and E1Physique + D("Physique") < E1Anglais, ("E1Anglais", "E1Physique"))#this should guarantee it doesn't overlap with the physics exam
problem.addConstraint(lambda E1Anglais, E1Maths: E1Anglais <= E1Maths and E1Anglais + D("Anglais") < E1Maths or E1Maths <= E1Anglais and E1Maths + D("Maths") < E1Anglais, ("E1Anglais", "E1Maths"))#this should guarantee it doesn't overlap with the math exam
#Contraintes un candidat par prof
problem.addConstraint(lambda E1Anglais, E2Anglais: E1Anglais <= E2Anglais and E1Anglais + D("Anglais") <= E2Anglais or E2Anglais <= E1Anglais and E2Anglais + D("Anglais") <= E1Anglais, ("E1Anglais", "E2Anglais")) #this should guarantee it doesn't overlap with other students' exams
problem.addVariable("E1Francais", range(1, 25-D("Francais"))) #add the French exam for the first student variable
#Contraintes une epreuve a la fois
problem.addConstraint(lambda E1Francais, E1Physique: E1Francais <= E1Physique and E1Francais + D("Francais") < E1Physique or E1Physique <= E1Francais and E1Physique + D("Physique") < E1Francais, ("E1Francais", "E1Physique")) #as you can see, I have one subject less for which I have to constraint the overlap since it's already been done in the constraints of the said subject, here we don't add the English hour variable
problem.addConstraint(lambda E1Francais, E1Maths: E1Francais <= E1Maths and E1Francais + D("Francais") < E1Maths or E1Maths <= E1Francais and E1Maths + D("Maths") < E1Francais, ("E1Francais", "E1Maths"))
#Contraintes un candidat par prof
problem.addConstraint(lambda E1Francais, E2Francais: E1Francais <= E2Francais and E1Francais + D("Francais") <= E2Francais or E2Francais <= E1Francais and E2Francais + D("Francais") <= E1Francais, ("E1Francais", "E2Francais"))
problem.addVariable("E1Physique", range(1, 25-D("Physique")))
#Contraintes une epreuve a la fois
problem.addConstraint(lambda E1Physique, E1Maths: E1Physique <= E1Maths and E1Physique + D("Physique") < E1Maths or E1Maths <= E1Physique and E1Maths + D("Maths") < E1Physique, ("E1Physique", "E1Maths"))
#Contraintes un candidat par prof
problem.addConstraint(lambda E1Physique, E2Physique: E1Physique <= E2Physique and E1Physique + D("Physique") <= E2Physique or E2Physique <= E1Physique and E2Physique + D("Physique") <= E1Physique, ("E1Physique", "E2Physique"))
problem.addVariable("E1Maths", range(1, 25-D("Maths")))
#Contraintes une epreuve a la fois
#Contraintes un candidat par prof
problem.addConstraint(lambda E1Maths, E2Maths: E1Maths <= E2Maths and E1Maths + D("Maths") <= E2Maths or E2Maths <= E1Maths and E2Maths + D("Maths") <= E1Maths, ("E1Maths", "E2Maths"))

solutions = problem.getSolutions()
print(solutions)