Depends on what you mean...
-If you want all the objects to move together (as if they were attached to each other), then you would create a parent object and drop that. Otherwise, you could merge all the data into one object.
-If you want all the objects to drop at once but behave separately upon collision, they need to be named differently and told to drop by the PY at the same time. You could either perform a loop within the PY or have a line for every object that you drop.