code: def flatten_dict(dd, separator=".", prefix=""):
      return (
          {
              prefix + separator + k if prefix else k: v
              for kk, vv in dd.items()
              for k, v in flatten_dict(vv, separator, kk).items()
          }
          if isinstance(dd, dict)
          else {prefix: dd}
      )
  
imports: import functools
  import threading
  import collections
  import contextlib
  import six
label_desc: Use image node_id 10 for calling a global function with example usage: flatten_dict(dd, separator, prefix) and returns: unknown