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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 _pfp__set_watch(self, watch_fields, update_func, *func_call_info):
 """Subscribe to update events on each field in ``watch_fields``, using ``update_func`` to update self's value when ``watch_field`` changes"""

        self._pfp__watch_fields = watch_fields

        for watch_field in watch_fields:
            watch_field._pfp__watch(self)
        self._pfp__update_func = update_func
        self._pfp__update_func_call_info = func_call_info