def revert(self, a):
        if a:
            return 1/a
        else:
            raise NotReversible('zero is not reversible')
Attach parents to the tree.
dataset/ETHPy150Open sympy/sympy/sympy/polys/domains/field.py/Field.revert--crossover with--dataset/ETHPy150Open spranesh/Redhawk/redhawk/common/tree_converter.py/TreeConverter.AttachParents