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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_group_value(self, token, match):
 """Return value of regex match for the specified group"""

        try:
            value = match.group('{}_{}'.format(token.name, self.group))
        except IndexError:
            value = ''
        return self.func(value) if callable(self.func) else value