get_size.py

import gc
import sys

def get_transitive_size(obj):
  stack = [obj]
  size = 0
  seen = set()
  while stack:
    o = stack.pop()
    if isinstance(o, type):
      continue
    size += sys.getsizeof(o)
    
    new_objs = set(gc.get_referents(o)) - seen
    seen.update(new_objs)
    stack.extend(new_objs)
  return size