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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 _add_overlays(self, config):
 """ Add this as a jobConfigOverlays JSON to config. """

        if self._comment:
            config['comment'] = self._comment

        jco = {}
        config["jobConfigOverlays"] = [jco]

        if self._raw_overlay:
            jco.update(self._raw_overlay)

        jc = jco.get('jobConfig', {})

        if self.job_name is not None:
            jc["jobName"] = self.job_name
        if self.job_group is not None:
            jc["jobGroup"] = self.job_group
        if self.data_directory is not None:
            jc["dataDirectory"] = self.data_directory
        if self.preload:
            jc['preloadApplicationBundles'] = True
        if self.tracing is not None:
            jc['tracing'] = self.tracing

        if self.submission_parameters:
             sp = jc.get('submissionParameters', [])
             for name in self.submission_parameters:
                  sp.append({'name': str(name), 'value': self.submission_parameters[name]})
             jc['submissionParameters'] = sp

        if jc:
            jco["jobConfig"] = jc

        if self.target_pe_count is not None and self.target_pe_count >= 1:
            deployment = jco.get('deploymentConfig', {})
            deployment.update({'fusionScheme' : 'manual', 'fusionTargetPeCount' : self.target_pe_count})
            jco["deploymentConfig"] = deployment
        return config