code: func (e *Instance) FromProto(c context.Context, p *api.Instance) *Instance {
  	e.InstanceID = common.ObjectRefToInstanceID(p.Instance)
  	e.Package = PackageKey(c, p.Package)
  	return e
  }
docs: // FromProto fills in the entity based on the proto message.
  //
  // Returns the entity itself for easier chaining.
  //
  // Doesn't touch output-only fields at all.