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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 mount(self, identifier):
 """ Mounts a container or image referred to by identifier to the host filesystem. """


        driver = self.client.info()['Driver']
        driver_mount_fn = getattr(self, "_mount_" + driver,
                                  self._unsupported_backend)
        cid = driver_mount_fn(identifier)

        # Return mount path so it can be later unmounted by path
        return self.mountpoint, cid