text: # -*- coding: utf-8 -*-
  
  # Copyright 2017, IBM.
  #
  # This source code is licensed under the Apache License, Version 2.0 found in
  # the LICENSE.txt file in the root directory of this source tree.
  
  """Quantum Information methods."""
  
  from .operators.operator import Operator
  from .operators.unitary import Unitary
  from .operators.pauli import Pauli, pauli_group
  from .operators.channel import Choi, SuperOp, Kraus, Stinespring, Chi, PTM
  from .operators.measures import process_fidelity
  from .states.states import basis_state, projector, purity
  from .states.measures import state_fidelity
  from .random import random_unitary, random_state, random_density_matrix
  