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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_evcodes_all(self, inc_set=None, exc_set=None):
 """Get set of evidence codes given include set and exclude set"""

        codes = self._get_grps_n_codes(inc_set) if inc_set else set(self.code2nt)
        if exc_set:
            codes.difference_update(self._get_grps_n_codes(exc_set))
        return codes