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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def walk_json_dict(coll):
 """ Flatten a parsed SBP object into a dicts and lists, which are compatible for JSON output. Parameters coll : dict """

  if isinstance(coll, dict):
    return dict((k, walk_json_dict(v)) for (k, v) in iter(coll.items()))
  elif isinstance(coll, bytes):
    return coll.decode('ascii')
  elif hasattr(coll, '__iter__') and not isinstance(coll, str):
    return [walk_json_dict(seq) for seq in coll]
  else:
    return coll