Strip datetime and other parts so that there is no redundancy.

def _strip_datetime(self, sub_line):
        """Strip datetime and other parts so that there is no redundancy."""
        try:
            begin = sub_line.index(']')
        except ValueError:
            return sub_line
        else:
            # create a "" in place character for the beginnings..
            # needed when interleaving the lists
            sub = sub_line[begin + 1:]
            return sub