connecting 2 objects by drawing a line without coordinates

Hi

I want to connect two objects/elements by using line from one node to another node without using any coordinates method.

eg:

4 objects are there

object 1 & 2 is having 2 two connecting nodes

object 3 & 4 is having one connecting nodes

Step1:

i want to connnect object_1 Second node to object_2 first node need to be connected

Step2:

i want to connnect object_1 First node to object_3 first node need to be connected

Step1:

i want to connnect object_2 Second node to object_4 first node need to be connected

is that below mentioned program is correct

i have the path/id for all objects node 

eg: 

if(obj_1 and obj2):

   obj_1.node2.click()

   obj_1.node2.drag(obj_2_n2)