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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 _ensure_pgrp(self):
 """Ensures that the pgrp file is present and up to date. There have been production cases where the file was lost or not immediately emitted due to disk space issues. """

        if not LAST_PGRP_PATH:  # global
            return
        try:
            with open(LAST_PGRP_PATH, 'w') as f:
                f.write(str(os.getpgrp()) + "\n")
        except IOError:
            # raised if no permissions or disk space
            pass