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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 run_build_model(self, num_runs=5, silent=False, force_rerun=False):
 """Run FoldX BuildModel command with a mutant file input. Original command:: foldx --command=BuildModel --pdb=4bxi_Repair.pdb --mutant-file=individual_list.txt --numberOfRuns=5 Args: num_runs (int):
 silent (bool):
 If FoldX output should be silenced from printing to the shell. force_rerun (bool):
 If FoldX BuildModel should be rerun even if the results file exists. """

        # BuildModel output files
        self.mutation_ddG_avg_outfile = 'Average_{}.fxout'.format(op.splitext(self.repaired_pdb_outfile)[0])
        self.mutation_ddG_raw_outfile = 'Raw_{}.fxout'.format(op.splitext(self.repaired_pdb_outfile)[0])

        # BuildModel command
        foldx_build_model = 'foldx --command=BuildModel --pdb={} --mutant-file={} --numberOfRuns={}'.format(self.repaired_pdb_outfile,
                                                                                                            op.basename(self.mutation_infile),
                                                                                                            num_runs)

        ssbio.utils.command_runner(shell_command=foldx_build_model, force_rerun_flag=force_rerun, silent=silent,
                                   outfile_checker=self.mutation_ddG_avg_outfile, cwd=self.foldx_dir)