With this script you can rename the children a null object, or any selection that has children inside, to match the parent's name + an incremental number, use in python scripts inside cinema. You can select any number of objects and it will rename the objects inside each parent to it's parent's name.

This is very useful when importing AI layers that have many paths inside.

import c4d

def main():
    # Get the active objects
    active_objects = doc.GetActiveObjects(c4d.GETACTIVEOBJECTFLAGS_CHILDREN)

    # Loop through each active object
    for obj in active_objects:
        # Get the name of the object
        base_name = obj.GetName()

        # Get the children of the object
        children = obj.GetChildren()

        # Loop through each child
        for i, child in enumerate(children):
            # Rename the child with the base name and an incremental number
            child.SetName(f"{base_name}_{i+1}")

    # Update the Cinema 4D scene
    c4d.EventAdd()

# Execute main()
if __name__=='__main__':
    main()