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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 qscan(self, cursor=0, count=None, busyloop=None, minlen=None, maxlen=None, importrate=None):
 """ Iterate all the existing queues in the local node. :param count: An hint about how much work to do per iteration. :param busyloop: Block and return all the elements in a busy loop. :param minlen: Don't return elements with less than count jobs queued. :param maxlen: Don't return elements with more than count jobs queued. :param importrate: Only return elements with an job import rate (from other nodes) >= rate. """

        command = ["QSCAN", cursor]
        if count:
            command += ["COUNT", count]
        if busyloop:
            command += ["BUSYLOOP"]
        if minlen:
            command += ["MINLEN", minlen]
        if maxlen:
            command += ["MAXLEN", maxlen]
        if importrate:
            command += ["IMPORTRATE", importrate]

        return self.execute_command(*command)