code: def append(self, bytes):
      with reset(self):
          written = self.write(bytes)
      return written
  
imports: import contextlib
  import io
  import os
  from uuid import uuid4
  import requests
  from .._compat import fields
label_desc: Use image node_id 4 for calling the CustomBytesIO obj's underlying member method code with example usage: obj.append(bytes) and returns: written