Retrieve the ipv4 address for this host ( optionally as seen from dest ).
    Example:
        addr = s_socket.hostaddr()

def hostaddr(dest='8.8.8.8'):
    '''
    Retrieve the ipv4 address for this host ( optionally as seen from dest ).
    Example:
        addr = s_socket.hostaddr()
    '''
    sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)

    # doesn't actually send any packets!
    sock.connect((dest, 80))
    addr, port = sock.getsockname()

    sock.close()

    return addr