YieldFrom

>>> print(ast.dump(ast.parse('yield x'), indent=4))
Module(
    body=[
        Expr(
            value=Yield(
                value=Name(id='x')))])

>>> print(ast.dump(ast.parse('yield from x'), indent=4))
Module(
    body=[
        Expr(
            value=YieldFrom(
                value=Name(id='x')))])