def _make_active_space_data(self, active_orbitals, reference=None):
    '\n        Small helper function\n        Internal use only\n        Parameters\n        ----------\n        active_orbitals: dictionary :\n            list: Give a list of spatial orbital indices\n            i.e. occ = [0,1,3] means that spatial orbital 0, 1 and 3 are used\n        reference: (Default value=None)\n            List of orbitals which form the reference\n            Can be given in the same format as active_orbitals\n            If given as None then the first N_electron/2 orbitals are taken\n            for closed-shell systems.\n\n        Returns\n        -------\n        Dataclass with active indices and reference indices (in spatial notation)\n\n        '
    if (active_orbitals is None):
        return None
    if (reference is None):
        assert ((self.n_electrons % 2) == 0)
        reference = sorted([i for i in range((self.n_electrons // 2))])
    return ActiveSpaceData(active_orbitals=sorted(active_orbitals), reference_orbitals=sorted(reference))
Small helper function
Internal use only
Parameters
----------
active_orbitals: dictionary :
    list: Give a list of spatial orbital indices
    i.e. occ = [0,1,3] means that spatial orbital 0, 1 and 3 are used
reference: (Default value=None)
    List of orbitals which form the reference
    Can be given in the same format as active_orbitals
    If given as None then the first N_electron/2 orbitals are taken
    for closed-shell systems.

Returns
-------
Dataclass with active indices and reference indices (in spatial notation)
def _make_active_space_data(self, active_orbitals, reference=None):
    '\n        Small helper function\n        Internal use only\n        Parameters\n        ----------\n        active_orbitals: dictionary :\n            list: Give a list of spatial orbital indices\n            i.e. occ = [0,1,3] means that spatial orbital 0, 1 and 3 are used\n        reference: (Default value=None)\n            List of orbitals which form the reference\n            Can be given in the same format as active_orbitals\n            If given as None then the first N_electron/2 orbitals are taken\n            for closed-shell systems.\n\n        Returns\n        -------\n        Dataclass with active indices and reference indices (in spatial notation)\n\n        '
    if (active_orbitals is None):
        return None
    if (reference is None):
        assert ((self.n_electrons % 2) == 0)
        reference = sorted([i for i in range((self.n_electrons // 2))])
    return ActiveSpaceData(active_orbitals=sorted(active_orbitals), reference_orbitals=sorted(reference))