PyTorch and Qiskit example from the Qiskit textbook seems broken

Question

After executing the proceeding code blocks, when I try to copy the same code from Qiskit textbook on my jupyter notebook, I get the error as

QiskitError: 'Data for experiment "circuit-109" could not be found.'

simulator = qiskit.Aer.get_backend('qasm_simulator')

circuit = QuantumCircuit(1, simulator, 100)
print('Expected value for rotation pi {}'.format(circuit.run([np.pi])[0]))
circuit._circuit.draw(
)

Please suggest:

<ipython-input-23-06b09ff4dd69> in <module>
      2 
      3 circuit = QuantumCircuit(1, simulator, 100)
----> 4 print('Expected value for rotation pi {}'.format(circuit.run([np.pi])[0]))
      5 circuit._circuit.draw()

<ipython-input-22-e6eb9c91d6f9> in run(self, thetas)
     28                         parameter_binds = [{self.theta: theta} for theta in thetas])
     29         job = self.backend.run(qobj)
---> 30         result = job.result().get_counts(self._circuit)
     31 
     32         counts = np.array(list(result.values()))

~\anaconda3\lib\site-packages\qiskit\result\result.py in get_counts(self, experiment)
    261         dict_list = []
    262         for key in exp_keys:
--> 263             exp = self._get_experiment(key)
    264             try:
    265                 header = exp.header.to_dict()

~\anaconda3\lib\site-packages\qiskit\result\result.py in _get_experiment(self, key)
    368 
    369             if len(exp) == 0:
--> 370                 raise QiskitError('Data for experiment "%s" could not be found.' %
    371                                   key)
    372             if len(exp) == 1:

QiskitError: 'Data for experiment "circuit-109" could not be found.'```

Answer 1

After checking, this issue was introduced in the last qiskit-terra release. The textbook should be fixed to adjust the get_counts, as already reported here.

In any case, the workaround for now is removing self._circuit from result = job.result().get_counts(self._circuit) (in QuantumCircuit.run method).

class QuantumCircuit:
    ...

    def run(self, thetas):
        ...
        job = self.backend.run(qobj)
        result = job.result().get_counts()  # <- here
        ...