class_docstr: Add Label as new guidance channel
  
  Args:
      source: label/source key which gets added as additional guidance channel
class_docstr_tok: ["Add","Label","as","new","guidance","channel","Args",":","source",":","label\/source","key","which","gets","added","as","additional","guidance","channel"]
code: def __init__(
      self, keys: KeysCollection, source: str = "label"
  ) -> None:
      super().__init__(keys, allow_missing_keys=False)
      self.source = source
  
imports: from __future__ import annotations
  import math
  from typing import Any
  import numpy
  import torch
  from monai.config import KeysCollection, NdarrayOrTensor
  from monai.networks.layers import GaussianFilter
  from monai.transforms import MapTransform, Randomizable, SpatialPad
  from monai.utils import StrEnum, convert_to_numpy, optional_import
label_desc: Use image node_id 1 to create a new AddLabelAsGuidanced object from inherited base classes: MapTransform with example: obj = AddLabelAsGuidanced(keys, source)