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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 _watch_callback(obj_weakref, method_name, *args, **kwargs):
 """ A callback handler for the ControlConnection that tolerates weak references. """

    obj = obj_weakref()
    if obj is None:
        return
    getattr(obj, method_name)(*args, **kwargs)