def gen_noise(batch_size, noise_shape):
    ''' Generates a numpy vector sampled from normal distribution of shape                                (batch_size,noise_shape)
    Input:
        batch_size : size of batch
        noise_shape: shape of noise vector, normally kept as 100
    Output:a numpy vector sampled from normal distribution of shape                                  (batch_size,noise_shape)
    '''
    return np.random.normal(0, 1, size=(batch_size,)+noise_shape)