code: def _euler_to_json(value, owner):
      if value is None:
          return None
      return _ieee_tuple_to_json(value[:3], owner) + [value[3]]
  
imports: from collections import namedtuple
  from collections.abc import Sequence
  import numbers
  import math
  import re
  import warnings
  from traitlets import Unicode, Int, CInt, Instance, Enum, List, Dict, Float, CFloat, Bool, Tuple, Undefined, TraitError, Union, TraitType, CaselessStrEnum
  from ipywidgets import widget_serialization
  from ipydatawidgets import DataUnion, NDArrayWidget, shape_constraints
  import numpy
label_desc: Use image node_id 5 for calling a global function with example usage: _euler_to_json(value, owner) and returns: unknown, None