code: def set_file(self, filename):
          
          # Use the file name as prefix if none is given
          if self.output_prefix is None:
              _, self.output_prefix = os.path.split(filename)
          # Check if the file is present, since rdpcap will not do that
          if not (os.path.isfile(filename) and os.access(filename, os.R_OK)):
              print 'The file \'{0}\' is either not present or not readable. '\
                    'Exiting!'.format(filename)
              sys.exit(1)
          try:
              packets = rdpcap(filename)
          except NameError:
              # Due probably to a bug in rdpcap, this kind of error raises a
              # NameError, because the exception that is tried to raise, is not
              # defined
              print 'The file \'{}\' is not a pcap capture file. Exiting!'\
                  .format(filename)
              sys.exit(2)
  
          for number, packet in enumerate(packets):
              # See if there is a field called load
              self._debug('\nNUMBER {0}'.format(number), no_prefix=True)
              try:
                  # Will cause AttributeError if there is no load
                  packet.getfieldval('load')
                  # Get the full load
                  load = packet.sprintf('%TCP.payload%')
                  self._debug('PAYLOAD LENGTH {0}'.format(len(load)),
                              no_prefix=True)
                  self._debug(load, load=True)
                  self._parse_load(load)
              except AttributeError:
                  self._debug('LOAD EXCEPTION', no_prefix=True)
          if len(self.messages) > 0 and not self.messages[-1].write_closed:
              self._debug('DELETE LAST OPEN FILE')
              del self.messages[-1]
  
          if self.args.debug_analysis:
              sys.exit(0)
docs: Analyse the file with the captured content