Fix deprecated warning

Author: manoelmarques

chemistry/h2_iqpe.ipynb

@@ -25,6 +25,8 @@
     "import multiprocessing as mp\n",
     "from qiskit import BasicAer\n",
     "from qiskit.aqua import QuantumInstance, AquaError\n",
+    "from qiskit.aqua.operators import Z2Symmetries\n",
+    "from qiskit.aqua.operators.op_converter import to_weighted_pauli_operator\n",
     "from qiskit.aqua.algorithms.single_sample import IQPE\n",
     "from qiskit.aqua.algorithms.classical import ExactEigensolver\n",
     "from qiskit.chemistry import FermionicOperator\n",
@@ -45,7 +47,7 @@
     "    molecule = driver.run()\n",
     "    qubit_mapping = 'parity'\n",
     "    fer_op = FermionicOperator(h1=molecule.one_body_integrals, h2=molecule.two_body_integrals)\n",
-    "    qubit_op = fer_op.mapping(map_type=qubit_mapping, threshold=1e-10).two_qubit_reduced_operator(2)\n",
+    "    qubit_op = Z2Symmetries.two_qubit_reduction(to_weighted_pauli_operator(fer_op.mapping(map_type=qubit_mapping, threshold=1e-10)), 2)\n",
     "\n",
     "    if algorithm.lower() == 'exacteigensolver':\n",
     "        exact_eigensolver = ExactEigensolver(qubit_op, k=1)\n",

chemistry/h2_qpe.ipynb

@@ -31,6 +31,8 @@
     "from qiskit.transpiler import PassManager\n",
     "from qiskit.aqua import AquaError\n",
     "from qiskit.aqua import QuantumInstance\n",
+    "from qiskit.aqua.operators import Z2Symmetries\n",
+    "from qiskit.aqua.operators.op_converter import to_weighted_pauli_operator\n",
     "from qiskit.aqua.algorithms import ExactEigensolver\n",
     "from qiskit.aqua.algorithms import QPE\n",
     "from qiskit.aqua.components.iqfts import Standard\n",
@@ -46,7 +48,7 @@
     "\n",
     "qubit_mapping = 'parity'\n",
     "fer_op = FermionicOperator(h1=molecule.one_body_integrals, h2=molecule.two_body_integrals)\n",
-    "qubit_op = fer_op.mapping(map_type=qubit_mapping,threshold=1e-10).two_qubit_reduced_operator(2)"
+    "qubit_op = Z2Symmetries.two_qubit_reduction(to_weighted_pauli_operator(fer_op.mapping(map_type=qubit_mapping, threshold=1e-10)), 2)"
    ]
   },
   {