Initialize the variables used for the peephole connections.

def _create_peephole_variables(self, dtype):
    """Initialize the variables used for the peephole connections."""
    self._w_f_diag = tf.get_variable(
        self.W_F_DIAG,
        shape=[self._hidden_size],
        dtype=dtype,
        initializer=self._initializers.get(self.W_F_DIAG),
        partitioner=self._partitioners.get(self.W_F_DIAG),
        regularizer=self._regularizers.get(self.W_F_DIAG))
    self._w_i_diag = tf.get_variable(
        self.W_I_DIAG,
        shape=[self._hidden_size],
        dtype=dtype,
        initializer=self._initializers.get(self.W_I_DIAG),
        partitioner=self._partitioners.get(self.W_I_DIAG),
        regularizer=self._regularizers.get(self.W_I_DIAG))
    self._w_o_diag = tf.get_variable(
        self.W_O_DIAG,
        shape=[self._hidden_size],
        dtype=dtype,
        initializer=self._initializers.get(self.W_O_DIAG),
        partitioner=self._partitioners.get(self.W_O_DIAG),
        regularizer=self._regularizers.get(self.W_O_DIAG))