utils.py 文件源码

def get_variable_trace_string(v):
    sio = StringIO()
    # For backward compatibility with old trace
    tr = getattr(v.tag, 'trace', [])
    if isinstance(tr, list) and len(tr) > 0:
        print(" \nBacktrace when that variable is created:\n", file=sio)
        # The isinstance is needed to handle old pickled trace
        if isinstance(tr[0], tuple):
            traceback.print_list(v.tag.trace, sio)
        else:
            # Print separate message for each element in the list of
            # batcktraces
            for subtr in tr:
                traceback.print_list(subtr, sio)
    return sio.getvalue()