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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 compile_loaderplugin_entry(self, spec, entry):
 """ Generic loader plugin entry handler. The default implementation assumes that everything up to the first '!' symbol resolves to some known loader plugin within the registry. The registry instance responsible for the resolution of the loader plugin handlers must be available in the spec under CALMJS_LOADERPLUGIN_REGISTRY """


        modname, source, target, modpath = entry
        handler = spec[CALMJS_LOADERPLUGIN_REGISTRY].get(modname)
        if handler:
            return handler(self, spec, modname, source, target, modpath)
        logger.warning(
            "no loaderplugin handler found for plugin entry '%s'", modname)
        return {}, {}, []