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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 _remove_untraceable(self):
 """Remove from the tracer those wires that CompiledSimulation cannot track. Create _probe_mapping for wires only traceable via probes. """

        self._probe_mapping = {}
        wvs = {wv for wv in self.tracer.wires_to_track if self._traceable(wv)}
        self.tracer.wires_to_track = wvs
        self.tracer._wires = {wv.name: wv for wv in wvs}
        self.tracer.trace.__init__(wvs)