The AST for DelayInstruction and QuantumBarrier defines a qubits attribute, but in oqpy we also use them for frames so the attribute naming is misleading. The typing is not an issue here.
@dataclass
class DelayInstruction(QuantumStatement):
"""
Delay instruction
Example::
delay[start_stretch] $0;
"""
duration: Expression
qubits: List[Union[IndexedIdentifier, Identifier]]
@dataclass
class QuantumBarrier(QuantumStatement):
"""
A quantum barrier instruction
Example::
barrier q;
"""
qubits: List[Expression]