class_docstr: Tests ``_default_wire_map`` helper function.
class_docstr_tok: ["Tests","``","_default_wire_map","``","helper","function","."]
docstr: Test wire map works with string labelled wires.
docstr_tok: ["Test","wire","map","works","with","string","labelled","wires","."]
code: def test_string_wires(self):
      """Test wire map works with string labelled wires."""
  
      ops = [qml.PauliY("a"), qml.CNOT(wires=("b", "c"))]
  
      wire_map = default_wire_map(ops)
      assert wire_map == {"a": 0, "b": 1, "c": 2}
  
imports: import pytest
  import pennylane
  from pennylane.drawer.utils import default_wire_map, default_bit_map, convert_wire_order, unwrap_controls, cwire_connections
  from pennylane.wires import Wires
label_desc: Use image node_id 3 for calling the TestDefaultWireMap obj's underlying member method code with example usage: obj.test_string_wires() without return types