I'm starting with Qiskit in Python.
My question is regarding to have registers and sub-register. Something like this
axreg=QuantumRegister(4,name='ax') ahreg=QuantumRegister(axreg[:2],name='ah') alreg=QuantumRegister(axreg[2:],name='al')
The constructor of QuantumRegister has only the number of qubits to create, and I find no way to add previously existing qubit to other register