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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 acquire_filename(self, name):
 """Acquire a file name and return its id and its signature. """


        id_ = self.__id_lut.get(name)
        # Is this a new entry?
        if id_ is None:
            # then create one...
            id_ = self.__next_id
            self.__next_id += 1
            self.__id_lut[name] = id_
            entry = filename_entry_t(name)
            self.__entries[id_] = entry
        else:
            # otherwise obtain the entry...
            entry = self.__entries[id_]

        entry.inc_ref_count()
        return id_, self._get_signature(entry)