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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def update_bucket_size(f):
 """Decorate to update bucket size after operation."""

    @wraps(f)
    def inner(self, *args, **kwargs):
        res = f(self, *args, **kwargs)
        self.bucket.size += self.file.size
        return res
    return inner