text: from __future__ import absolute_import, division, print_function
  
  from dxtbx.format.FormatPYunspecified import FormatPYunspecified
  
  class FormatPYCXI31(FormatPYunspecified):
  
    """PREFERENCE FILE.
       Treats any Pickle-format file lacking a DETECTOR_FORMAT_VERSION key
       automatically as format CXI 3.1.
       Rename this file to FormatPYCXI31.py and put in dxtbx/format path.
    """
  
    def _start(self):
  
      FormatPYunspecified.start_helper(self,version_token="distl.detector_format_version=CXI 3.1")
  
  if __name__ == '__main__':
  
    import sys
  
    for arg in sys.argv[1:]:
      print(FormatPYCXI31.understand(arg))
  