docstr: Test the output of combining expval, var and counts
docstr_tok: ["Test","the","output","of","combining","expval",",","var","and","counts"]
code: def test_counts_combination(self):
      """Test the output of combining expval, var and counts"""
      n_sample = 10
  
      dev = qml.device("default.qubit", wires=3, shots=n_sample)
  
      @qml.qnode(dev, diff_method="parameter-shift")
      def circuit():
          qml.RX(0.54, wires=0)
  
          return (
              qml.counts(qml.PauliZ(0)),
              qml.expval(qml.PauliX(1)),
              qml.var(qml.PauliY(2)),
          )
  
      result = circuit()
  
      assert len(result) == 3
      assert sum(result[0].values()) == n_sample
  
imports: import copy
  import numpy
  import pytest
  import pennylane
  from pennylane.measurements import AllCounts, Counts, CountsMP
  from pennylane.wires import Wires
label_desc: Use image node_id 3 for calling the TestCountsIntegration obj's underlying member method code with example usage: obj.test_counts_combination() and returns: qml,  qml,  qml