为什么在读取一个空文件时出现“ Pickle-EOFError：Ran out of input”的问题？

我先检查文件是否为空：

import osscores = {} # scores is an empty dict alreadyif os.path.getsize(target) > 0:          with open(target, "rb") as f:        unpickler = pickle.Unpickler(f)        # if file is not empty scores will be equal        # to the value unpickled        scores = unpickler.load()

而且

open(target, 'a').close()

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