# Getting specs using catalyst
**URL:** https://discuss.pennylane.ai/t/getting-specs-using-catalyst/3845
**Category:** PennyLane Development
**Created:** [December 22, 2023, 4:35pm UTC](https://discuss.pennylane.ai/t/getting-specs-using-catalyst/3845 "2023-12-22T16:35:35Z")
**Posts on this page:** 2
**Page:** 1
### Author:  [@Mushahid\_Khan](https://discuss.pennylane.ai/u/Mushahid_Khan)
#### Post date: [December 22, 2023, 4:35pm UTC](https://discuss.pennylane.ai/t/getting-specs-using-catalyst/3845/1 "2023-12-22T16:35:36Z")
Hi,
I am trying to get the specs for a catalyst program but i am getting an error when i try to get the specs. Here is the code. What could be causing this?:
```auto
from catalyst import qjit, measure
import pennylane as qml
from jax import numpy as jnp
@qjit
@qml.qnode(qml.device("lightning.qubit", wires=5))
def circuit():
qml.CNOT([0,1])
measure(0)
return qml.expval(qml.PauliZ(0))
qml.specs(circuit)()
```
* * *
AttributeError Traceback (most recent call last)
in \()
10 return qml.expval(qml.PauliZ(0))
11
—\> 12 qml.specs(circuit)()
/usr/local/lib/python3.10/dist-packages/pennylane/transforms/specs.py in specs\_qnode(\*args, \*\*kwargs)
112 qnode.max\_expansion = initial\_max\_expansion if max\_expansion is None else max\_expansion
113 qnode.expansion\_strategy = expansion\_strategy or initial\_expansion\_strategy
→ 114 qnode.construct(args, kwargs)
115 finally:
116 qnode.max\_expansion = initial\_max\_expansion
AttributeError: ‘QJIT’ object has no attribute ‘construct’
---
### Author:  [@Ivana\_at\_Xanadu](https://discuss.pennylane.ai/u/Ivana_at_Xanadu)
#### Post date: [January 10, 2024, 10:39am UTC](https://discuss.pennylane.ai/t/getting-specs-using-catalyst/3845/2 "2024-01-10T10:39:19Z")
Hey, @Mushahid_Khan. So `qjit` gives you a [QJIT object](https://docs.pennylane.ai/projects/catalyst/en/stable/code/api/catalyst.qjit.html), but `qml.specs` needs to be run on a [QNode](https://docs.pennylane.ai/en/stable/code/api/pennylane.specs.html).
I think the best you can do to get the specs is to forgo the qjit-ing on the circuit you’re looking at. With the most recent (this week’s) PennyLane and Catalyst versions ([v0.34 and v0.4](https://pennylane.ai/blog/2024/01/pennylane-release-0.34/)), you can do this:
```auto
import pennylane as qml
from catalyst import measure
@qml.qnode(qml.device("lightning.qubit", wires=5))
def circuit():
qml.CNOT([0,1])
qml.measure(0)
return qml.expval(qml.PauliZ(0))
qml.specs(circuit)()
```
But if you’d want to qjit without getting to the specs, your circuit would look like this:
```auto
@qml.qjit
@qml.qnode(qml.device("lightning.qubit", wires=5))
def circuit():
qml.CNOT([0,1])
measure(0)
return qml.expval(qml.PauliZ(0))
```
Is there a specific reason you’d want to have the specs while running qjit?
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