execute function does not recognize ScheduleBlock

Information

• Qiskit Terra version: main
• Python version: N/A
• Operating system: N/A

What is the current behavior?

When pulse.build produces a ScheduleBlock and it is submitted to be executed by the backend via execute(schedule_block, backend) an error AttributeError: 'ScheduleBlock' object has no attribute 'calibrations' . is raised.

Steps to reproduce the problem

# Importing standard Qiskit libraries
from qiskit import QuantumCircuit, transpile, Aer, IBMQ, pulse, execute

provider = IBMQ.load_account()
backend = provider.get_backend("ibmq_armonk")

with pulse.build() as sched_block:
    pulse.play(pulse.Constant(160, 1.0), pulse.DriveChannel(0))

execute(sched_block, backend)

What is the expected behavior?

Execute should accept a ScheduleBlock as well as execute and this should be submitted to backend.run.

Suggested solutions

Within execute when matching on Schedule instead match on a Union[Schedule, ScheduleBlock].

[jakelishman]

I think this is a bug in Terra’s FakeBackend caller - #7059. Abby: PulseSystemModel is in Aer (qiskit-aer/qiskit/providers/aer/pulse/system_models/pulse_system_mode.py), so it doesn’t appear in the Terra repo.

[mtreinish]

We also only install aer on a subset of ci jobs and only from a release on pypi. We do this very specifically to avoid adding an accidental bidirectional dependency between aer and terra (where aer depends on aer and aer depends on terra, even if just for testing) because the dependency should only be in a single direction (and aer depends on terra).