def METHOD_NAME(self):
    m = pyo.ConcreteModel()
    m.fs = pyo.Block()
    m.fs.x = pyo.Var(initialize=-0.5)
    m.fs.a = pyo.Param(initialize=1.0, mutable=True)
    m.fs.b = pyo.Param(initialize=2.0, mutable=False)
    m.fs.sum = pyo.Expression(expr=m.fs.a + m.fs.x)
    m.fs.lim = pyo.Constraint(expr=m.fs.sum >= 0.0)
    m.fs.obj = pyo.Objective(expr=m.fs.x, sense=pyo.minimize)
    return m