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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 flg(self, name, help, abbrev=None):
 """Describe a flag"""

        abbrev = abbrev or '-' + name[0]
        longname = '--' + name.replace('_', '-')
        self._add(name, abbrev, longname, action='store_true', help=help)