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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 delete(self, uuid):
 # type: (UUID) -> None """Delete file with given uuid. :param:uuid: :class:`UUID` instance :raises:KeyError if file does not exists """

        dest = self.abs_path(uuid)
        if not dest.exists():
            raise KeyError("No file can be found for this uuid", uuid)

        dest.unlink()