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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 _try_weakref(arg, remove_callback):
 """Return a weak reference to arg if possible, or arg itself if not."""

    try:
        arg = weakref.ref(arg, remove_callback)
    except TypeError:
        # Not all types can have a weakref. That includes strings
        # and floats and such, so just pass them through directly.
        pass
    return arg