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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 merge_qpoints(self, workdir, files_to_merge, out_prefix):
 """ Execute mrgscr inside directory `workdir` to merge `files_to_merge`. Produce new file with prefix `out_prefix` """

        # We work with absolute paths.
        files_to_merge = [os.path.abspath(s) for s in list_strings(files_to_merge)]
        nfiles = len(files_to_merge)

        if self.verbose:
            print("Will merge %d files with output_prefix %s" % (nfiles, out_prefix))
            for (i, f) in enumerate(files_to_merge):
                print(" [%d] %s" % (i, f))

        if nfiles == 1:
            raise self.Error("merge_qpoints does not support nfiles == 1")

        self.stdin_fname, self.stdout_fname, self.stderr_fname = \
            map(os.path.join, 3 * [workdir], ["mrgscr.stdin", "mrgscr.stdout", "mrgscr.stderr"])

        inp = StringIO()
        inp.write(str(nfiles) + "\n")     # Number of files to merge.
        inp.write(out_prefix + "\n")      # Prefix for the final output file:

        for filename in files_to_merge:
            inp.write(filename + "\n")   # List with the files to merge.

        inp.write("1\n")                 # Option for merging q-points.

        self.stdin_data = [s for s in inp.getvalue()]

        with open(self.stdin_fname, "w") as fh:
            fh.writelines(self.stdin_data)
            # Force OS to write data to disk.
            fh.flush()
            os.fsync(fh.fileno())

        self.execute(workdir)