_file.py 263 B

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  1. a = open('123.txt', 'wt')
  2. a.write('123')
  3. a.write('456')
  4. a.close()
  5. with open('123.txt', 'rt') as f:
  6. assert f.read() == '123456'
  7. with open('123.txt', 'a') as f:
  8. f.write('测试')
  9. with open('123.txt', 'r') as f:
  10. assert f.read() == '123456' + '测试'