From sympy.physics.quantum.hilbert https://github.com/sympy/sympy/blob/master/sympy/physics/qua... :

  __all__ = [
    'HilbertSpaceError',
    'HilbertSpace',
    'TensorProductHilbertSpace',
    'TensorPowerHilbertSpace',
    'DirectSumHilbertSpace',
    'ComplexSpace',
    'L2',
    'FockSpace'
  ]

  __all__ = [
    'Operator',
    'HermitianOperator',
    'UnitaryOperator',
    'IdentityOperator',
    'OuterProduct',
    'DifferentialOperator'
  ]

  """ A module for mapping operators to their corresponding eigenstates and vice versa
  It contains a global dictionary with eigenstate-operator pairings.
  If a new state-operator pair is created,
  this dictionary should be updated as well.
  It also contains functions operators_to_state and state_to_operators for mapping between the two. These can handle both classes and instances of operators and states. 
  See the individual function descriptions for details.
  TODO List:
  - Update the dictionary with a complete list of state-operator pairs
  """

  """Logic for representing operators in state in various bases.
  
  TODO:
  * Get represent working with continuous hilbert spaces.
  * Document default basis functionality.
  """
  # ...
  
  __all__ = [
    'represent',
    'rep_innerproduct',
    'rep_expectation',
    'integrate_result',
    'get_basis',
    'enumerate_states'
  ]
  
  # ...
  
  def represent(expr, **options):
      """Represent the quantum expression in the given basis.

From tequila/simulators/simulator_cirq https://github.com/tequilahub/tequila/blob/master/src/tequil... :

  from tequila.wavefunction.qubit_wavefunction import QubitWaveFunction

> """ Export QCircuits as qasm code OPENQASM version 2.0 specification from:

> A. W. Cross, L. S. Bishop, J. A. Smolin, and J. M. Gambetta, e-print arXiv:1707.03429v2 [quant-ph] (2017). https://arxiv.org/pdf/1707.03429v2.pdf