code: func ValidateLeaseSpec(spec *coordination.LeaseSpec, fldPath *field.Path) field.ErrorList {
  	allErrs := field.ErrorList{}
  
  	if spec.LeaseDurationSeconds != nil && *spec.LeaseDurationSeconds <= 0 {
  		fld := fldPath.Child("leaseDurationSeconds")
  		allErrs = append(allErrs, field.Invalid(fld, spec.LeaseDurationSeconds, "must be greater than 0"))
  	}
  	if spec.LeaseTransitions != nil && *spec.LeaseTransitions < 0 {
  		fld := fldPath.Child("leaseTransitions")
  		allErrs = append(allErrs, field.Invalid(fld, spec.LeaseTransitions, "must to greater or equal than 0"))
  	}
  	return allErrs
  }
docs: // ValidateLeaseSpec validates spec of Lease.