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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 update_mandb(self, quiet=True):
 """Update mandb."""

        if not environ.config.UpdateManPath:
            return
        print('\nrunning mandb...')
        cmd = 'mandb %s' % (' -q' if quiet else '')
        subprocess.Popen(cmd, shell=True).wait()