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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 list2str(self, l: List, joiner: str) -> str: """ Convert list to str as input for tokenizer Args: l (list):
 list for converting joiner (str):
 join the elements using this string to separate them. Returns: the value of the list as a string """

        result = str()
        for item in l:
            if isinstance(item, list):
                result = result + self.list2str(item, joiner) + joiner
            elif isinstance(item, dict):
                result = result + self.dict2str(item, joiner) + joiner
            elif item:
                result = result + str(item) + joiner
        return result