Extended the from_backend method of InstructionDurations to support both BackendV1 and BackendV2

[shravanpatel30]

Summary

This PR fixes #12760

I have extended the from_backend method of InstructionDurations so that it supports both BackendV1 and BackendV2 (also GenericBackendV2). To get the instruction durations from the BackendV2, I have used the attribute target. Also, in GenericBackendV2, the (duration, error) for delay and reset is set to (None, None) and this None value raises an error in the update() method of InstructionDurations. So, I am skipping the instructions which have None as the duration (let me know if this is not what we want).

@1ucian0, please review this and let me know if this is acceptable. If you want I can also add tests and/or new release notes for the changes I have made.

Thanks

Details and comments

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Pull Request Test Coverage Report for Build 10428323140

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Details

• 3 of 3 (100.0%) changed or added relevant lines in 1 file are covered.
• 449 unchanged lines in 23 files lost coverage.
• Overall coverage decreased (-0.2%) to 89.558%

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Files with Coverage Reduction	New Missed Lines	%
crates/accelerate/src/two_qubit_decompose.rs	1	90.69%
qiskit/providers/fake_provider/fake_pulse_backend.py	1	95.24%
qiskit/synthesis/unitary/qsd.py	1	97.58%
qiskit/transpiler/passes/synthesis/unitary_synthesis.py	2	88.39%
qiskit/providers/fake_provider/fake_qasm_backend.py	2	95.65%
qiskit/compiler/transpiler.py	3	92.39%
qiskit/transpiler/passmanager_config.py	3	95.95%
qiskit/transpiler/passes/scheduling/padding/dynamical_decoupling.py	4	94.86%
qiskit/transpiler/preset_passmanagers/common.py	5	89.5%
qiskit/synthesis/two_qubit/xx_decompose/decomposer.py	6	90.84%

Totals
Change from base Build 10339507099:	-0.2%
Covered Lines:	67577
Relevant Lines:	75456

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💛 - Coveralls

[Cryoris]

Thanks for the contribution! However I think there's a simpler way of solving this, see the comments below 🙂 Also, yes, this would need a releasenote (under fixes) and a test (for which you could use the example from #12760)

[Cryoris]

Backend includes BackendV2 so we don't need an extra type here 🙂

[Cryoris]

I think we could just solve this as

def from_backend(cls, backend):
    if isinstance(backend, BackendV2):
        return backend.target.durations()
        
    # old code goes here as it is

[shravanpatel30]

Hi @Cryoris, thanks for reviewing the PR. I have incorporated the changes that you requested. Let me know if I need to make any more edits.

Thanks

[Cryoris]

Suggested change

	The `from_backend` method of :class:`.InstructionDurations` now allows extracting instruction durations from both `BackendV1` and `BackendV2`.
	Fixed a bug where :meth:`.InstructionDurations.from_backend` did not work for :class:`.BackendV2` backends.
	Fixed `#12760 <https://github.com/Qiskit/qiskit/issues/12760>`__.

[shravanpatel30]

Hi @Cryoris, I have edited the releasenote as per your comment.

[ElePT]

The fix looks good to me, and it looks like you applied all of @Cryoris's suggestions, thanks @shravanpatel30! We can probably backport it to 1.2 too, I'll add the stable backport label.

[shravanpatel30]

Hi @ElePT, I received an email that this pull request was removed from merge queue. Do I need to make any changes to this pull request?

Thanks

[ElePT]

This was probably due to unrelated status check issues, I'll re-queue and keep an eye on the PR. No action needed @shravanpatel30 :)