title: Custom weight initialization tensorflow tf.layers.dense
body: <p>I'm trying to set up custom initializer to <code>tf.layers.dense</code> where I initialize <code>kernel_initializer</code> with a weight matrix I already have.</p>
  
  <pre><code>u_1 = tf.placeholder(tf.float32, [784, 784])
  first_layer_u = tf.layers.dense(X_, n_params, activation=None, 
                                kernel_initializer=u_1,
                                bias_initializer=tf.keras.initializers.he_normal())
  </code></pre>
  
  <p>This is throwing error saying <code>ValueError: If initializer is a constant, do not specify shape.</code></p>
  
  <p>Is it a problem to assign placeholder to <code>kernel_initializer</code> or am I missing something?</p>