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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_series(self, series):
 """ Returns a census series API handler. """

        if series == "acs1":
            return self.census.acs1dp
        elif series == "acs5":
            return self.census.acs5
        elif series == "sf1":
            return self.census.sf1
        elif series == "sf3":
            return self.census.sf3
        else:
            return None