This procedure replaces every line which can't be parsed
    with special object MalformedLogEntry.

def log_analyzer(path):
    """This procedure replaces every line which can't be parsed
    with special object MalformedLogEntry.
    """
    with handle(MalformedLogEntryError,
                  lambda (c):
                      invoke_restart('use_value',
                                     MalformedLogEntry(c.text))):
        for filename in find_all_logs(path):
            analyze_log(filename)