Verifies a subset of the arguments to create()

def _verify_create_args(module_name, class_name, static):
    """ Verifies a subset of the arguments to create() """
    # Verify module name is provided
    if module_name is None:
        raise InvalidServiceConfiguration(
            'Service configurations must define a module'
        )

    # Non-static services must define a class
    if not static and class_name is None:
        tmpl0 = 'Non-static service configurations must define a class: '
        tmpl1 = 'module is %s'
        raise InvalidServiceConfiguration((tmpl0 + tmpl1) % module_name)