class_docstr: A single stack frame along with sum of memory usage at the frame.
  
  Attributes:
      stackframe (FrameSummary): stackframe from traceback.extract_stack().
      parent (MemoryFrame): parent frame, that is, caller.
      children (list of MemoryFrame): child frames, that is, callees.
      used_bytes (int): memory bytes that users used from CuPy memory pool.
      acquired_bytes (int): memory bytes that CuPy memory pool acquired
          from GPU device.
class_docstr_tok: ["A","single","stack","frame","along","with","sum","of","memory","usage","at","the","frame",".","Attributes",":","stackframe","(","FrameSummary",")",":","stackframe","from","traceback.extract_stack","(",")",".","parent","(","MemoryFrame",")",":","parent","frame",",","that","is",",","caller",".","children","(","list","of","MemoryFrame",")",":","child","frames",",","that","is",",","callees",".","used_bytes","(","int",")",":","memory","bytes","that","users","used","from","CuPy","memory","pool",".","acquired_bytes","(","int",")",":","memory","bytes","that","CuPy","memory","pool","acquired","from","GPU","device","."]
code: def __init__(self, parent, stackframe):
      self.stackframe = stackframe
      self.children = []
      self._set_parent(parent)
      self.used_bytes = 0
      self.acquired_bytes = 0
  
imports: from os import path
  import sys
  import traceback
  from cupy.cuda import memory_hook
label_desc: Use image node_id 1 to create a new MemoryFrame object from inherited base classes: object with example: obj = MemoryFrame(parent, stackframe)