read LEON:
print(`A  basis for the polynomials annihilated by the operators`):
print(D1^2+D2^2,D1+D2):
print(`of degree<=2.`):
print(`is: `):
print(PolSols([D1^2+D2^2,D1+D2],[x1,x2],[D1,D2],2)):
print(`This took `, time() , `seconds `):
quit: