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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 get_file_ids(self, file_list, creator=None, status=FileStatus.no_file, file_dict=None):
 """Get or create a list of file ids based on file names Parameters file_list : list The paths to the file creatror : int A unique key for the job that created these files status : `FileStatus` Enumeration giving current status of files file_dict : `FileDict` Mask giving flags set on this file Returns list of integers """

        ret_list = []
        for fname in file_list:
            if file_dict is None:
                flags = FileFlags.no_flags
            else:
                flags = file_dict.file_dict[fname]
            try:
                fhandle = self.get_handle(fname)
            except KeyError:
                if creator is None:
                    creator = -1
                    # raise KeyError("Can not register a file %s without a creator"%fname)
                fhandle = self.register_file(fname, creator, status, flags)
            ret_list.append(fhandle.key)
        return ret_list