Skip to content
Qubitra SDK

List backends

examples/list_backends.py

The problem

Section titled “The problem”

Every integration starts with the same two questions: which backends can this API key reach, and what does each of them accept? This example answers both in one screen — the backend catalogue with each entry’s type, qubit count and availability, followed by the marketplace offerings.

The walkthrough

Section titled “The walkthrough”
from qubitra import QubitraClient

QubitraClient reads QUBITRA_API_KEY and QUBITRA_API_URL from the environment, so the example needs no configuration code of its own.

def main() -> None:
    with QubitraClient() as client:
        for backend in client.backends.list():
            kind = backend.type.value if backend.type else "?"
            qubits = f"{backend.qubit_count}q" if backend.qubit_count else ""
            state = "available" if backend.available else "unavailable"
            print(f"{backend.id:32} {kind:10} {qubits:6} {state:12} {backend.name or ''}")

client.backends.list() returns the whole catalogue this key can reach. The guards on type and qubit_count matter: capability fields are absent until known, so a backend whose metadata has yet to sync carries None there, and the example prints it as ? or an empty column.

        print()
        for offering in client.marketplace.offerings():
            print(f"{offering.id:38} {offering.type.value:14} {offering.name or ''}")

client.marketplace.offerings() lists the marketplace’s published offerings — the applications, tools and backends available to acquire — with each one’s type and name.

Running it

Section titled “Running it”
Terminal window
QUBITRA_API_KEY=qpk_... python examples/list_backends.py

The output is one line per backend — id, type, qubit count, availability, display name — then a blank line and one line per marketplace offering. The catalogue is the deployment’s own, so the exact rows depend on where you point QUBITRA_API_URL; a dev stack shows the seeded simulators, sim-statevector-26q among them.

Where to go next

Section titled “Where to go next”