Python 可以使用pexpect获取输出直到超时，而不查找任何特定模式吗

我已经生成了一个telnet会话。我想得到会话在给定时间间隔内抛出的任何输出。如何使用pexpect实现它。 我尝试了expect（'.*'，20）。但这将匹配在此时间之前输出的任何内容，并且不会等待超时20秒

# set expected to some string you might not see
def ReadByDuration(connection, expected = ".*", read_time = 20, epsilon = 0.001):
    from time import time
    start_time = time()
    response = connection.read_until(expected,float(read_time))
    time_passed = time() - start_time 
    # if timeout not met, read again
    while read_time - time_passed > epsilon :
        response += connection.read_until(expected, float(read_time  - time_passed))
        time_passed = time() - start_time
    return response

如果你想变得更有趣，你可以把它添加到类函数中

import telnetlib, types
t = telnetlib.Telnet(IP, PORT, 20)
t.ReadByDuration = types.MethodType( ReadByDuration, t )

t.ReadByDuration(".*", 20)