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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 serialize(self, obj, level=0, objname=None, topLevelKeysToIgnore=None, toBytes=True):
 """ Create a string representation of the given object. Examples: :: 'str' '1,2,3,4,5' '1:a|2:b' '1:a|2:b|3:1,2:k' :param obj: the object to serlize :param level: a parameter used internally for recursion to serialize nested data structures :param topLevelKeysToIgnore: the list of top level keys to ignore for serialization :return: a string representation of `obj` """

        res = None
        if not isinstance(obj, acceptableTypes):
            error("invalid type found {}: {}".format(objname, obj))
        elif isinstance(obj, str):
            res = obj
        elif isinstance(obj, dict):
            if level > 0:
                keys = list(obj.keys())
            else:
                topLevelKeysToIgnore = topLevelKeysToIgnore or []
                keys = [k for k in obj.keys() if k not in topLevelKeysToIgnore]
            keys.sort()
            strs = []
            for k in keys:
                onm = ".".join([str(objname), str(k)]) if objname else k
                strs.append(
                    str(k) + ":" + self.serialize(obj[k], level + 1, onm, toBytes=False))
            res = "|".join(strs)
        elif isinstance(obj, Iterable):
            strs = []
            for o in obj:
                strs.append(self.serialize(
                    o, level + 1, objname, toBytes=False))
            res = ",".join(strs)
        elif obj is None:
            res = ""
        else:
            res = str(obj)

        # logger.trace("serialized msg {} into {}".format(obj, res))

        if not toBytes:
            return res

        return res.encode('utf-8')