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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 _to_json_default(obj):
 """Helper to convert non default objects to json. Usage: simplejson.dumps(data, default=_to_json_default) """

    # Datetime
    if isinstance(obj, datetime.datetime):
        return obj.isoformat()

    # UUID
    if isinstance(obj, uuid.UUID):
        return str(obj)

    # numpy
    if hasattr(obj, 'item'):
        return obj.item()

    # # Enum
    # if hasattr(obj, 'value'):
    #     return obj.value

    try:
        return obj.id
    except Exception:
        raise TypeError('{obj} is not JSON serializable'.format(obj=repr(obj)))