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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 meraculous_runner(self):
 """ Check to make sure that the allAssembliesDir has been created, if not, make it. This will only execute for the first time an assembly has been run in this directory. Run the directory from allAssembliesDir. The self.callString instance attribute tells Meraculous to name the assembly directory self.runName. After the run is complete, create the meraculous report, passing the directory containing the run (aka self.thisAssemblyDir). """

        #set the dir to temp assembly dir
        os.chdir(self.allAssembliesDir)

        print(self.callString)
        p = subprocess.run(self.callString, shell=True, stdout=subprocess.PIPE,
                           stderr=subprocess.PIPE,
                           universal_newlines=True)
        output = str(p.stdout)
        err = str(p.stderr)

        #generate the report for the run
        self._generate_report()

        #exit, returning the output and err
        return (output, err)