code: def _not_fixed_qubits(n_qubits_circuit, exclude, length):
      """
      Function that returns all possible combinations of qubits given some restrictions and using itertools.
      Args:
          n_qubits_circuit (int): Number of qubit in the circuit.
          exclude (list): list of qubits from the first matched circuit operation that needs to be excluded.
          length (int): length of the list to be returned (number of qubits in pattern -
          number of qubits from the first matched operation).
      Yield:
          iterator: Iterator of the possible lists.
      """
      circuit_range = range(0, n_qubits_circuit)
      for sublist in itertools.combinations(
          [e for e in circuit_range if e not in exclude], length
      ):
          yield list(sublist)
  
imports: import copy
  import itertools
  from collections import OrderedDict
  from typing import Sequence, Callable
  import numpy
  import pennylane
  from pennylane.transforms import transform
  from pennylane import adjoint
  from pennylane.ops.qubit.attributes import symmetric_over_all_wires
  from pennylane.tape import QuantumTape, QuantumScript
  from pennylane.transforms.commutation_dag import commutation_dag
  from pennylane.wires import Wires
label_desc: Use image node_id 4 for calling a global function with example usage: _not_fixed_qubits(n_qubits_circuit, exclude, length) without return types