'Initialize the Layer Norm LSTM cell.
Args:
num_units: int, The number of units in the LSTM cell.
forget_bias: float, The bias added to forget gates (default 1.0).
use_recurrent_dropout: Whether to use Recurrent Dropout (default False)
dropout_keep_prob: float, dropout keep probability (default 0.90)'

def __init__(self, num_units, forget_bias=1.0, use_recurrent_dropout=False, dropout_keep_prob=0.9):

    self.num_units = num_units
    self.forget_bias = forget_bias
    self.use_recurrent_dropout = use_recurrent_dropout
    self.dropout_keep_prob = dropout_keep_prob
