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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 rd_files(self, study_fn, pop_fn):
 """Read files and return study and population."""

        study, pop = self._read_geneset(study_fn, pop_fn)
        print("Study: {0} vs. Population {1}\n".format(len(study), len(pop)))
        return study, pop