Fix python lint

qiskit/circuit/parametertable.py

@@ -12,9 +12,8 @@
 """
 Look-up table for variable parameters in QuantumCircuit.
 """
-import operator
-import typing
-from collections.abc import MappingView, MutableMapping, MutableSet
+
+from collections.abc import MappingView
 
 
 class ParameterView(MappingView):

qiskit/circuit/quantumcircuit.py

@@ -2484,13 +2484,10 @@ def _append(self, instruction, qargs=(), cargs=()):
             # clear cache if new parameter is added
             self._parameters = None
 
-        self._track_operation(instruction.operation)
-        return instruction.operation if old_style else instruction
-
-    def _track_operation(self, operation: Operation):
-        """Sync all non-data-list internal data structures for a newly tracked operation."""
+        # Invalidate whole circuit duration if an instruction is added
         self.duration = None
         self.unit = "dt"
+        return instruction.operation if old_style else instruction
 
     @typing.overload
     def get_parameter(self, name: str, default: T) -> Union[Parameter, T]: ...
@@ -4026,7 +4023,7 @@ def global_phase(self, angle: ParameterValueType):
         """
         # If we're currently parametric, we need to throw away the references.  This setter is
         # called by some subclasses before the inner `_global_phase` is initialised.
-        if isinstance(previous := getattr(self._data, "global_phase", None), ParameterExpression):
+        if isinstance(getattr(self._data, "global_phase", None), ParameterExpression):
             self._parameters = None
         if isinstance(angle, ParameterExpression):
             if angle.parameters:
@@ -6566,7 +6563,8 @@ def append(self, instruction):
     def extend(self, data: CircuitData):
         self.circuit._data.extend(data)
         self.circuit._parameters = None
-        data.foreach_op(self.circuit._track_operation)
+        self.circuit.duration = None
+        self.circuit.unit = "dt"
 
     def resolve_classical_resource(self, specifier):
         # This is slightly different to cbit_argument_conversion, because it should not

qiskit/circuit/quantumcircuitdata.py

@@ -20,8 +20,6 @@
 from .exceptions import CircuitError
 from .instruction import Instruction
 from .operation import Operation
-from .instruction import Instruction
-from .gate import Gate
 
 
 CircuitInstruction = qiskit._accelerate.circuit.CircuitInstruction

test/python/circuit/test_circuit_data.py

@@ -831,8 +831,6 @@ def test_param_gate_instance(self):
         # A fancy way of doing qc0_instance = qc0.data[0] and qc1_instance = qc1.data[0]
         # but this at least verifies the parameter table is point from the parameter to
         # the correct instruction (which is the only one)
-        param_entry_0 = qc0._data._get_param(b.uuid.int)
-        param_entry_1 = qc1._data._get_param(a.uuid.int)
         qc0_instance = qc0._data[next(iter(qc0._data._get_param(b.uuid.int)))[0]]
         qc1_instance = qc1._data[next(iter(qc1._data._get_param(a.uuid.int)))[0]]
         self.assertNotEqual(qc0_instance, qc1_instance)

test/python/circuit/test_rust_equivalence.py

@@ -14,14 +14,13 @@
 
 from math import pi
 
+from test import QiskitTestCase
+
 import numpy as np
 
 from qiskit.circuit import QuantumCircuit
 from qiskit.circuit.library.standard_gates import get_standard_gate_name_mapping
 
-from test import QiskitTestCase
-
-
 SKIP_LIST = {"cy", "ccx", "rx", "ry", "ecr", "sx"}
 CUSTOM_MAPPING = {"x", "rz"}