return Undefined for consistency
return Undefined for consistency

Regarding the TODO: although hi <= upto works, e.g. y <= Min(4, y) the simplification
requires some delicacy (according to sympy.live.org):

```
>>> from sympy.solvers.inequalities import _solve_inequality as f
>>> f(y<=Piecewise((y,y<=4),(4,True)),y)
And(-oo < y, y < oo)
>>> f(y<=Piecewise((y,y<4),(4,True)),y)
And(y <= 4, -oo < y)
>>> f(y<Piecewise((y,y<=4),(4,True)),y)
False
>>> f(y<Piecewise((y,y<4),(4,True)),y)
False
```

==> solving this depends on how Min gets rewritten as Piecewise
kaushik94/sympy,kaushik94/sympy,kaushik94/sympy