问Tensorflow- bidirectional_dynamic_rnn:尝试重用RNNCell

EN

import tensorflow as tf
import numpy as np

tf.reset_default_graph()

# Create input data
X = np.random.randn(2, 10, 8)

# The second example is of length 6 
X[1,6:] = 0
X_lengths = [10, 6]

cell = tf.contrib.rnn.LSTMCell(num_units=64, state_is_tuple=True)

outputs, states  = tf.nn.bidirectional_dynamic_rnn(
    cell_fw=cell,
    cell_bw=cell,
    dtype=tf.float64,
    sequence_length=X_lengths,
    inputs=X)

output_fw, output_bw = outputs
states_fw, states_bw = states

ValueError: Attempt to reuse RNNCell <tensorflow.contrib.rnn.python.ops.core_rnn_cell_impl.LSTMCell object at 0x10ce0c2b0> 
with a different variable scope than its first use.  First use of cell was with scope 
'bidirectional_rnn/fw/lstm_cell', this attempt is with scope 'bidirectional_rnn/bw/lstm_cell'.  
Please create a new instance of the cell if you would like it to use a different set of weights.  
If before you were using: MultiRNNCell([LSTMCell(...)] * num_layers), change to:
 MultiRNNCell([LSTMCell(...) for _ in range(num_layers)]).  If before you were using the same cell 
 instance as both the forward and reverse cell of a bidirectional RNN, simply create two instances 
 (one for forward, one for reverse).  In May 2017, we will start transitioning this cell's behavior to use 
 existing stored weights, if any, when it is called with scope=None (which can lead to silent model degradation, 
 so this error will remain until then.)