docstr: Set fit-compute function at the specified port.
  
  Parameters
  ----------
  port
      Port on which to set the fit-compute function.
  
  value
      fit-compute function of the step. Pass ``None`` to disable it.
code: def set_fit_compute_func_at(
      self, port: int, value: Optional[Callable]
  ):
      """Set fit-compute function at the specified port.
  
      Parameters
      ----------
      port
          Port on which to set the fit-compute function.
  
      value
          fit-compute function of the step. Pass ``None`` to disable it.
      """
      self._nodes[port].fit_compute_func = value
  
imports: import inspect
  import warnings
  from typing import Any, Callable, Dict, List, Optional, Union, TYPE_CHECKING
  from baikal._core.data_placeholder import DataPlaceholder, is_data_placeholder_list
  from baikal._core.utils import listify, make_name, make_repr
label_desc: Use image node_id 25 for calling the _StepBase obj's underlying member method code with example usage: obj.set_fit_compute_func_at(port, value) without return types