`CircuitToEinsum` fails for some qiskit `QuantumCircuit`

[derwind]

Informations

Python 3.10.12 (Google Colab) qiskit 0.45.0 qiskit-terra 0.45.0 cuquantum-python 23.10.0 cuquantum-python-cu11 23.10.0

What is the current behavior?

Recently, qiskit 0.45.0 was released. According to its release note:

Starting in this release, all unparametrized gates in the Qiskit standard circuit library are now singletons.

This changed the type of CXGate from <class 'qiskit.circuit.library.standard_gates.x.CXGate'> to <class '_SingletonCXGate'>.

So, get_decomposed_gates of circuit_parser_utils_qiskit.py fails if CXGate is used since the condition of #L42 is now False: if 'standard_gate' in str(type(operation)) or isinstance(operation, UnitaryGate):

Steps to reproduce the problem

Executing snippets below leads to AttributeError: 'NoneType' object has no attribute 'qubits' at #L56.

from qiskit import QuantumCircuit
from cuquantum import CircuitToEinsum


qc = QuantumCircuit(2)
qc.cx(0, 1)
converter = CircuitToEinsum(qc)