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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 listtransactions(self, user_id="", count=10, start_at=0):
 """List all transactions associated with this account. Args: user_id (str):
 this user's unique identifier count (int):
 number of transactions to return (default=10) start_at (int):
 start the list at this transaction (default=0) Returns: list [dict]: transactions associated with this user's account """

        txlist = self.rpc.call("listtransactions", user_id, count, start_at)
        self.logger.debug("Got transaction list for " + str(user_id))
        return txlist