class_docstr: Tests for simple single-qutrit observables
class_docstr_tok: ["Tests","for","simple","single-qutrit","observables"]
docstr: Test that the label is correct
docstr_tok: ["Test","that","the","label","is","correct"]
code: def test_label(self, index):
      """Test that the label is correct"""
  
      label = f"GellMann({index})"
      obs = qml.GellMann(wires=0, index=index)
  
      assert obs.label() == label
      assert obs.label(decimals=2) == label
  
imports: import functools
  from unittest.mock import PropertyMock, patch
  import pytest
  import numpy
  from gate_data import GELL_MANN
  import pennylane
label_desc: Use image node_id 6 for calling the TestGellMann obj's underlying member method code with example usage: obj.test_label(index) without return types