In Python M2Crypto I cannot set the socket timeout over 30 seconds

Question

I have tried

from M2Crypto import SSL
handle = url_opener.open(theurl, urllib.urlencode(data), SSL.timeout(120))

also

c = SSL.Connection(ctx)
c.set_socket_read_timeout(SSL.timeout(120))

also

SSL.Connection.set_socket_read_timeout(c, SSL.timeout(120))  

I can set the timeout less than 30 seconds but not more than 30 seconds.