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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 _disk_setter(self, variable, value):
 """ Use by disk image setter for checking and apply modifications :param variable: Variable name in the class :param value: New disk value """

        value = self.manager.get_abs_image_path(value)
        if not self.linked_clone:
            for node in self.manager.nodes:
                if node != self and getattr(node, variable) == value:
                    raise QemuError("Sorry a node without the linked base setting enabled can only be used once on your server. {} is already used by {}".format(value, node.name))
        setattr(self, "_" + variable, value)
        log.info('QEMU VM "{name}" [{id}] has set the QEMU {variable} path to {disk_image}'.format(name=self._name,
                                                                                                   variable=variable,
                                                                                                   id=self._id,
                                                                                                   disk_image=value))