def assert_tf_version(minimum_tf_version=MINIMUM_TF_VERSION, blacklisted=BLACKLISTED_TF_VERSIONS):
    """ Assert that the Tensorflow version is up to date.
    """
    detected = tf.version.VERSION
    required = '.'.join(map(str, minimum_tf_version))
    assert(tf_version_ok(minimum_tf_version, blacklisted)), 'You are using tensorflow version {}. The minimum required version is {} (blacklisted: {}).'.format(detected, required, blacklisted)
 Assert that the Tensorflow version is up to date.
    
keras_retinanet/utils/tf_version.py