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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 open_orders(self, symbol=None):
 """Get open orders via HTTP. Used on close to ensure we catch them all."""

        api = "order"
        query = {'ordStatus.isTerminated': False }
        if symbol != None:
            query['symbol'] =symbol
        orders = self._curl_bitmex(
            api=api,
            query={'filter': json.dumps(query)},
            verb="GET"
        )
        return orders