docstr: Set the fit-compute function of the step.
  
  You can use this only when the step has been called exactly once.
  
  Parameters
  ----------
  value
      fit-compute function of the step. Pass ``None`` to disable it.
  
  Raises
  ------
  AttributeError
      If the step has not been called yet or it is a shared step
      (called several times).
code: def fit_compute_func(self, value: Optional[Callable]):
      """Set the fit-compute function of the step.
  
      You can use this only when the step has been called exactly once.
  
      Parameters
      ----------
      value
          fit-compute function of the step. Pass ``None`` to disable it.
  
      Raises
      ------
      AttributeError
          If the step has not been called yet or it is a shared step
          (called several times).
      """
      self._set_step_attr("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 16 for calling the _StepBase obj's underlying member method code with example usage: obj.fit_compute_func(value) without return types