new_contents: #!/usr/bin/env python
  from write_xml import write_to_file
  
  # ''' This is just for single test of one function write_to_file
  # Because I found that the generated xml is not compatiable with
  # original xml, containing the head `<?xml xxx>`, this may harm
  # r-cnn code and it crashes when finishing parsing
  #'''
  
  write_to_file("aaa.xml", "orange", "stest.xml", "480", "640", "0", "0", "123", "123")
  
subject: add single test to debug the string issue