code: def test_exceptions_observable(fermion_ops, mapping, msg_match):
      """Test that the 'observable' function throws an exception if any element
      in the list 'fermion_ops' is not a FermionOperator objector or if the
      fermionic-to-qubit transformation is not properly defined."""
  
      with pytest.raises(TypeError, match=msg_match):
          qchem.observable(fermion_ops, mapping=mapping)
  
imports: import sys
  import pytest
  import pennylane
  from pennylane import qchem
label_desc: Use image node_id 2 for calling a global function with example usage: test_exceptions_observable(fermion_ops, mapping, msg_match) without return types