func defaultPolicyPath(sys *types.SystemContext) string {
	if sys != nil {
		if sys.SignaturePolicyPath != "" {
			return sys.SignaturePolicyPath
		}
		if sys.RootForImplicitAbsolutePaths != "" {
			return filepath.Join(sys.RootForImplicitAbsolutePaths, systemDefaultPolicyPath)
		}
	}
	return systemDefaultPolicyPath
}
func defaultPolicyPath(sys *types.SystemContext) string {
	if sys != nil {
		if sys.SignaturePolicyPath != "" {
			return sys.SignaturePolicyPath
		}
		if sys.RootForImplicitAbsolutePaths != "" {
			return filepath.Join(sys.RootForImplicitAbsolutePaths, systemDefaultPolicyPath)
		}
	}
	return systemDefaultPolicyPath
}
// defaultPolicyPath returns a path to the default policy of the system.