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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(self, list_id=None, email_address=None, include_tracking_preference=False):
 """Gets a subscriber by list ID and email address."""

        params = {
            "email": email_address or self.email_address,
            "includetrackingpreference": include_tracking_preference,
        }
        response = self._get("/subscribers/%s.json" %
                             (list_id or self.list_id), params=params)
        return json_to_py(response)