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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 rpc_connect(self):
 """Connect to a coin daemon's JSON RPC interface. Returns: bool: True if successfully connected, False otherwise. """

        if self.coin in COINS:
            rpc_url = COINS[self.coin]["rpc-url"] + ":"
            if self.testnet:
                rpc_url += COINS[self.coin]["rpc-port-testnet"]
            else:
                rpc_url += COINS[self.coin]["rpc-port"]
            self.rpc = pyjsonrpc.HttpClient(
                url=rpc_url,
                username=COINS[self.coin]["rpc-user"],
                password=COINS[self.coin]["rpc-password"]
            )
            self.logger.debug(self.coin, "RPC connection ok")
            self.connected = True
        else:
            self.logger.debug(self.coin, "bridge not found")
        return self.connected