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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 _nailgunnable_combined_classpath(self):
 """Register all of the component tools of the rsc compile task as a "combined" jvm tool. This allows us to invoke their combined classpath in a single nailgun instance (see #7089 and #7092). We still invoke their classpaths separately when not using nailgun, however. """

    cp = []
    cp.extend(self.tool_classpath('rsc'))
    # Add zinc's classpath so that it can be invoked from the same nailgun instance.
    cp.extend(super(RscCompile, self).get_zinc_compiler_classpath())
    return cp