def prepare_hardcore_boson_reference(self):
    U = gates.X(target=[i for i in range((self.n_electrons // 2))])
    U.n_qubits = self.n_orbitals
    return U
def prepare_hardcore_boson_reference(self):
    U = gates.X(target=[i for i in range((self.n_electrons // 2))])
    U.n_qubits = self.n_orbitals
    return U