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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 _GenerateFleetspeakConfig(self, template_dir, rpm_build_dir):
 """Generates a Fleetspeak config for GRR."""

    source_config = os.path.join(
        template_dir, "fleetspeak",
        os.path.basename(
            config.CONFIG.Get(
                "ClientBuilder.fleetspeak_config_path", context=self.context)))
    fleetspeak_service_dir = config.CONFIG.Get(
        "ClientBuilder.fleetspeak_service_dir", context=self.context)
    dest_config_dir = os.path.join(rpm_build_dir, fleetspeak_service_dir[1:])
    utils.EnsureDirExists(dest_config_dir)
    dest_config_path = os.path.join(
        dest_config_dir,
        config.CONFIG.Get(
            "Client.fleetspeak_unsigned_config_fname", context=self.context))
    self.GenerateFile(
        input_filename=source_config, output_filename=dest_config_path)