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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 set_input_fields(self, input_fields):
 """Given a scalar or ordered list of strings generate JSONPaths that describe how to access the values necessary for the Extractor """

        if not (isinstance(input_fields, basestring) or
                isinstance(input_fields, types.ListType)):
            raise ValueError("input_fields must be a string or a list")
        self.input_fields = input_fields
        self.generate_json_paths()
        return self