import tensorflow as tf

        with tf.variable_scope(name) :
            self.w = tf.get_variable('w',[input_dim, output_dim],
                                initializer=tf.random_normal_initializer(stddev=stddev))
            self.b = tf.get_variable('b',[output_dim],
                                initializer=tf.constant_initializer(0.0))

    def __call__(self,input_var,name=None,w=None,b=None,**kwargs) :
        w = w if w is not None else self.w
