[New Hint] IS_QUAD_RESIDUE

[pefontana]

                "from starkware.crypto.signature.signature import FIELD_PRIME",
                "from starkware.python.math_utils import div_mod, is_quad_residue, sqrt",
                "",
                "x = ids.x",
                "if is_quad_residue(x, FIELD_PRIME):",
                "    ids.y = sqrt(x, FIELD_PRIME)",
                "else:",
                "    ids.y = sqrt(div_mod(x, 3, FIELD_PRIME), FIELD_PRIME)"

#715