R = singular.ring(0,'(Ψ,Ω,α)','ds')
---------------------------------------------------------------------------
SingularError                             Traceback (most recent call last)
<ipython-input-361-30b6da8019fd> in <module>()
----> 1 R = singular.ring(Integer(0),'(Ψ,Ω,α)','ds')

/opt/sagemath-8.6/local/lib/python2.7/site-packages/sage/interfaces/singular.pyc in ring(self, char, vars, order, check)
   1049             s = '; '.join(['if(defined(%s)>0){kill %s;};'%(x,x)
   1050                            for x in vars[1:-1].split(',')])
-> 1051             self.eval(s)
   1052
   1053         if check and isinstance(char, integer_types + (sage.rings.integer.Integer,)):

/opt/sagemath-8.6/local/lib/python2.7/site-packages/sage/interfaces/singular.pyc in eval(self, x, allow_semicolon, strip, **kwds)
    658         # Singular actually does use that string
    659         if s.find("error occurred") != -1 or s.find("Segment fault") != -1:
--> 660             raise SingularError('Singular error:\n%s'%s)
    661
    662         if get_verbose() > 0:

SingularError: Singular error:
   ? `N` is not defined
   ? error occurred in or before STDIN line 12791: `(N()>0){kill N(;};; if(defined(N))>0){kill N);};; if(defined(N1)>0){kill N1;};`
   ? error occurred in or before STDIN line 12791: `(N()>0){kill N(;};; if(defined(N))>0){kill N);};; if(defined(N1)>0){kill N1;};`
   ? last reserved name was `defined`
   skipping text from `0`

> ring rr = 0,(x1,x_2,x(3)),dp;
> maxideal(1)^2;
_[1]=x1^2
_[2]=x1*x_2
_[3]=x1*x(3)
_[4]=x_2^2
_[5]=x_2*x(3)
_[6]=x(3)^2

> ring rgreek = 0,(alpha,beta,gamma),dp;
> maxideal(1)^2;
_[1]=alpha^2
_[2]=alpha*beta
_[3]=alpha*gamma
_[4]=beta^2
_[5]=beta*gamma
_[6]=gamma^2