通过捕获所有 socket.error 异常，并在 errno 时重新引发它 属性不等于 111.或者，更好的是，使用 errno.ECONNREFUSED 改为常量:

By catching all socket.error exceptions, and re-raising it if the errno attribute is not equal to 111. Or, better yet, use the errno.ECONNREFUSED constant instead:

import errno
from socket import error as socket_error

try:
    senderSocket.send('Hello')
except socket_error as serr:
    if serr.errno != errno.ECONNREFUSED:
        # Not the error we are looking for, re-raise
        raise serr
    # connection refused
    # handle here