如何修改TensorFlow-Hub模块中的可训练tf.Variables以使用自定义内核初始化器？

import tensorflow as tf
import tensorflow_hub as hub

def custom_initializer(shape, dtype=None):
    # 在这里实现您自定义的内核初始化逻辑
    # 返回一个初始化后的张量
    return tf.constant(0.5, shape=shape, dtype=dtype)

module_url = "https://tfhub.dev/google/nnlm-en-dim128/1"
embed = hub.Module(module_url)

module_vars = tf.get_collection(tf.GraphKeys.GLOBAL_VARIABLES, scope="module_name")
for var in module_vars:
    if "kernel" in var.name:
        var.initializer = custom_initializer

inputs = tf.placeholder(dtype=tf.string, shape=[None])
outputs = embed(inputs)