code: def vi_change_param(self, index, value):
          
          if index == 0:
              self.mu0 = value
          elif index == 1:
              self.sigma0 = np.exp(value)
docs: Wrapper function for changing latent variables - variational inference
  
          Parameters
          ----------
          index : int
              0 or 1 depending on which latent variable
  
          value : float
              What to change the latent variable to