code: def run_spp(self, input_bam, output, plot, cpus):
          
          base = "{} {} -rf -savp".format(self.tools.Rscript, self.tools.spp)
          cmd = base + " -savp={} -s=0:5:500 -c={} -out={} -p={}".format(
              plot, input_bam, output, cpus)
          return cmd
docs: Run the SPP read peak analysis tool.
  
          :param str input_bam: Path to reads file
          :param str output: Path to output file
          :param str plot: Path to plot file
          :param int cpus: Number of processors to use
          :return str: Command with which to run SPP