def bond_force_bond
import bend-prot@0.1.0.0/bonded.bend as Bondedimport Base
import bend-prot@0.1.0.0/geom.bend as G
import bend-prot@0.1.0.0/protein.bend as P
296def bond_force_bond(+xs: List<&2, P.Atom>, s: U32, +a: U32, +b: U32, +k: F32) -> G.Vec3:
297 bond_force_look(s, atom_of_serial(xs, a), atom_of_serial(xs, b), a, b, k)