我必须与csv文件进行比较，我需要删除重复的行并生成另一个文件。

#here I´m comparing the csv files. The oldest_file and the newest_file
different_data_type = newest_file.equals(other = oldest_file)

#If they have differences, I concat them to drop those rows that are equals
merged_files = pd.concat([oldest_file, newest_file])
        
merged_files = merged_files.drop_duplicates()
print(merged_files())

每个csv文件大约有5. 000行，当我打印merged_files时，我收到了一个10. 000行的csv文件。换句话说，它不会掉。
如何只获取有差异的行？