docs: def compute_inv_covariance(L_aug, Y, k, p):
      """Given label matrix L and labels Y, compute the covariance.
  
      Args:
          L: (np.array) [n, d] The augmented (indicator) label matrix
          Y: (np.array int) [n] The true labels in {1,...,k}
      """
      return np.linalg.inv(compute_covariance(L_aug, Y, k, p))