code: def get_ast_field_name(ast):
      
      replacements = {
          # We always rewrite the following field names into their proper underlying counterparts.
          TYPENAME_META_FIELD_NAME: '@class'
      }
      base_field_name = ast.name.value
      normalized_name = replacements.get(base_field_name, base_field_name)
      return normalized_name
docs: Return the normalized field name for the given AST node.