old_contents: example_template = Template({
      'A': RsrcDef({}, []),
      'B': RsrcDef({}, []),
      'C': RsrcDef({}, ['A', 'B']),
      'D': RsrcDef({'c': GetRes('C')}, []),
      'E': RsrcDef({'ca': GetAtt('C', 'a')}, []),
  })
  engine.create_stack('foo', example_template)
  
new_contents: example_template = Template({
      'A': RsrcDef({}, []),
      'B': RsrcDef({}, []),
      'C': RsrcDef({'a': '4alpha'}, ['A', 'B']),
      'D': RsrcDef({'c': GetRes('C')}, []),
      'E': RsrcDef({'ca': GetAtt('C', 'a')}, []),
  })
  engine.create_stack('foo', example_template)
  
subject: Fix up properties/attributes in basic_create scenario