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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 req(self, method, params=()):
 """send request to ppcoind"""


        response = self.session.post(
            self.url,
            data=json.dumps({"method": method, "params": params, "jsonrpc": "1.1"}),
        ).json()

        if response["error"] is not None:
            return response["error"]
        else:
            return response["result"]