class_docstr: Dictionary-based wrapper of :py:class:`monai.apps.pathology.transforms.array.GenerateWatershedMarkers`.
  
  Args:
      mask_key: the input key where the watershed mask is stored. Defaults to `"mask"`.
      border_key: the input key where instance border map is stored. Defaults to `"border"`.
      markers_key: the output key where markers is written. Defaults to `"markers"`.
      threshold: threshold the float values of instance border map to int 0 or 1 with specified threshold.
          It turns uncertain area to 1 and other area to 0. Defaults to 0.4.
      radius: the radius of the disk-shaped footprint used in `opening`. Defaults to 2.
      min_object_size: objects smaller than this size are removed. Defaults to 10.
      postprocess_fn: execute additional post transformation on marker. Defaults to None.
      dtype: target data content type to convert, default is np.uint8.
      allow_missing_keys: don't raise exception if key is missing.
code: def __call__(
      self, data: Mapping[Hashable, NdarrayOrTensor]
  ) -> dict[Hashable, NdarrayOrTensor]:
      d = dict(data)
      if self.markers_key in d:
          raise KeyError(
              f"The key '{self.markers_key}' for markers already exists."
          )
      d[self.markers_key] = self.transform(
          d[self.mask_key], d[self.border_key]
      )
      return d
  
imports: from __future__ import annotations
  from collections.abc import Callable, Hashable, Mapping
  import numpy
  import torch
  from monai.apps.pathology.transforms.post.array import GenerateDistanceMap, GenerateInstanceBorder, GenerateInstanceCentroid, GenerateInstanceContour, GenerateInstanceType, GenerateSuccinctContour, GenerateWatershedMarkers, GenerateWatershedMask, HoVerNetInstanceMapPostProcessing, HoVerNetNuclearTypePostProcessing, Watershed
  from monai.config.type_definitions import DtypeLike, KeysCollection, NdarrayOrTensor
  from monai.transforms.transform import MapTransform, Transform
  from monai.utils import optional_import
  from monai.utils.enums import HoVerNetBranch
label_desc: Use image node_id 2 for calling the GenerateWatershedMarkersd obj's underlying member method code with example usage: obj.__call__(data) and returns: d