Describe the bug

Error while training detection model：
"RuntimeError: The default implementation of deepcopy() for wrapper subclasses only works for subclass types that implement clone() and for which cloning returns another instance of the same subclass. You should either properly implement clone() for your subclass or override deepcopy() if it is intended behavior for clone() to return an instance of a different type."

Further debugging revealed that it was the deepcopy function that reported an error on a MetaTensor variable if it was empty size.