Validates the template and parameter values and raises exceptions if there's an issue

        :param dict sam_template: SAM template

def _validate(self, sam_template):
        """ Validates the template and parameter values and raises exceptions if there's an issue

        :param dict sam_template: SAM template
        """

        if "Resources" not in sam_template or not isinstance(sam_template["Resources"], dict) \
                or not sam_template["Resources"]:
            raise InvalidDocumentException(
                [InvalidTemplateException("'Resources' section is required")])

        SamTemplateValidator.validate(sam_template)