old_contents: #   Licensed under the Apache License, Version 2.0 (the "License");
  #   you may not use this file except in compliance with the License.
  #   You may obtain a copy of the License at
  #
  #       http://www.apache.org/licenses/LICENSE-2.0
  #
  #   Unless required by applicable law or agreed to in writing, software
  #   distributed under the License is distributed on an "AS IS" BASIS,
  #   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  #   See the License for the specific language governing permissions and
  #   limitations under the License.
  
  from ._binary_code_transform import (binary_code_transform,
                                       dissolve)
  from ._bksf import bravyi_kitaev_fast
  from ._bravyi_kitaev import bravyi_kitaev
  from ._binary_code_transform import (binary_code_transform,
                                       dissolve)
  from ._code_transform_functions import (bravyi_kitaev_code,
                                          checksum_code,
                                          interleaved_code,
                                          jordan_wigner_code,
                                          parity_code,
                                          weight_two_segment_code,
                                          weight_one_binary_addressing_code,
                                          weight_one_segment_code)
  from ._conversion import (get_fermion_operator,
                            get_interaction_rdm,
                            get_interaction_operator,
                            get_quadratic_hamiltonian,
                            get_molecular_data,
                            get_sparse_operator)
  from ._jordan_wigner import jordan_wigner
  from ._reverse_jordan_wigner import reverse_jordan_wigner
  from ._verstraete_cirac import verstraete_cirac_2d_square
  
new_contents: #   Licensed under the Apache License, Version 2.0 (the "License");
  #   you may not use this file except in compliance with the License.
  #   You may obtain a copy of the License at
  #
  #       http://www.apache.org/licenses/LICENSE-2.0
  #
  #   Unless required by applicable law or agreed to in writing, software
  #   distributed under the License is distributed on an "AS IS" BASIS,
  #   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  #   See the License for the specific language governing permissions and
  #   limitations under the License.
  
  from ._binary_code_transform import (binary_code_transform,
                                       dissolve)
  from ._bksf import bravyi_kitaev_fast
  from ._bravyi_kitaev import bravyi_kitaev
  from ._code_transform_functions import (bravyi_kitaev_code,
                                          checksum_code,
                                          interleaved_code,
                                          jordan_wigner_code,
                                          parity_code,
                                          weight_two_segment_code,
                                          weight_one_binary_addressing_code,
                                          weight_one_segment_code)
  from ._conversion import (get_fermion_operator,
                            get_interaction_rdm,
                            get_interaction_operator,
                            get_quadratic_hamiltonian,
                            get_molecular_data,
                            get_sparse_operator)
  from ._jordan_wigner import jordan_wigner
  from ._reverse_jordan_wigner import reverse_jordan_wigner
  from ._verstraete_cirac import verstraete_cirac_2d_square
  
subject: remove extra import statement (#243)