def METHOD_NAME(block_diag_operator):
    # We take the cholesky of each block on the diagonal.
  return linear_operator_block_diag.LinearOperatorBlockDiag(
      operators=[
          operator.cholesky() for operator in block_diag_operator.operators],
      is_non_singular=True,
      is_self_adjoint=False,
      is_square=True)