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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 get_opt(self, opt):
 """Get value of option from configuration file Parameters opt : string Name of option (e.g. output-file-format) Returns -------- value : string The value for the option. Returns None if option not present. """

        for sec in self.sections:
            try:
                key = self.cp.get(sec, opt)
                if key:
                    return key
            except ConfigParser.NoOptionError:
                pass

        return None