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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 prepare_spec(self, spec, **kwargs):
 """ Prepare a spec for usage with the generic ToolchainRuntime. Subclasses should avoid overriding this; override create_spec instead. """


        self.prepare_spec_debug_flag(spec, **kwargs)
        self.prepare_spec_export_target_checks(spec, **kwargs)
        # defer the setup till the actual toolchain invocation
        spec.advise(SETUP, self.prepare_spec_advice_packages, spec, **kwargs)