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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 prepare_args(self, args, transform=True):
 """Prepare args to be used by a sub-index Parameters args: list transform: bool If ``True``, the last entry in `args`, ie the value, will be transformed. Else it will be kept as is. """

        updated_args = list(args)
        if transform:
            updated_args[-1] = self.transform_value(updated_args[-1])
        if self.key:
            updated_args.insert(-1, self.key)

        return updated_args