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