def validate_templates(self, value):
manager = TemplateManager(settings.RAFEE_REPO_DIR)
bad_template_names = []
for template_name in value.split(","):
if not manager.template_exists(template_name):
bad_template_names.append(template_name)
if len(bad_template_names) > 0:
raise serializers.ValidationError(TEMPLATES_NOT_FOUND.format(bad_template_names))
return value
