如何解决谢谢

代码如下:

from paddle import fluid
a = fluid.layers.fill_constant(shape=[2,1],dtype='int64',value=5)
b = fluid.layers.fill_constant(shape=[2,1],dtype='int64',value=6)

ifcond = fluid.layers.less_than(x=a,y=b)
ie = fluid.layers.IfElse(ifcond)
with ie.true_block():
c = ie.input(a)
c += 1
ie.output(c)

exe = fluid.Executor(fluid.CPUPlace())#CPU上执行传入

exe.run(fluid.default_main_program(),fetch_list=[c])

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Error: Cannot find fetch variable in scope, fetch_var_name is tmp_0 at (D:\1.7.1\paddle\paddle\fluid\operators\controlflow\fetch_op.cc:38)
[operator < fetch > error]