code: def __init__(self, manager: MemoryManager):
      self.manager = manager
      self.mmap = None
  
file_path: ffcv/ffcv/memory_managers/os_cache.py
imports: from typing import TYPE_CHECKING
  import numpy
  import numba
  from .base import MemoryManager, MemoryContext
  from ..pipeline.compiler import Compiler
label_desc: Use image node_id 1 to create a new OSCacheContext object from inherited base classes: MemoryContext with example: obj = OSCacheContext(manager)