code: def set_log_file_extension(self, logFileExtension):
          
          assert isinstance(logFileExtension, basestring), "logFileExtension must be a basestring"
          assert len(logFileExtension), "logFileExtension can't be empty"
          if logFileExtension[0] == ".":
              logFileExtension = logFileExtension[1:]
          assert len(logFileExtension), "logFileExtension is not allowed to be single dot"
          if logFileExtension[-1] == ".":
              logFileExtension = logFileExtension[:-1]
          assert len(logFileExtension), "logFileExtension is not allowed to be double dots"
          self.__logFileExtension = logFileExtension
          # set log file name
          self.__set_log_file_name()
docs: Set the log file extension.
  
          :Parameters:
             #. logFileExtension (string): Logging file extension. A logging file full name is
                set as logFileBasename.logFileExtension