def make_net(self, netmask):
        """Transform a single IP address into a network specification by
        applying the given netmask.

        Returns a new IP instance.

        >>> print(IP('127.0.0.1').make_net('255.0.0.0'))
        127.0.0.0/8
        """
        if str(netmask) in '/':
            raise ValueError("invalid netmask (%s)" % netmask)
        return IP('%s/%s' % (self, netmask), make_net=True)
dataset/ETHPy150Open fp7-ofelia/ocf/ofam/src/src/foamext/IPy.py/IP.make_net/swapped operands of `in`