class_docstr: Potentially composite object, for testing.
class_docstr_tok: ["Potentially","composite","object",",","for","testing","."]
code: def fit(self):
      if hasattr(self.foo_, "fit"):
          self.foo_.fit()
      self._is_fitted = True
  
imports: from copy import deepcopy
  import pytest
  from sktime.base import BaseEstimator, BaseObject
  from sktime.utils.validation._dependencies import _check_soft_dependencies
label_desc: Use image node_id 2 for calling the FittableCompositionDummy obj's underlying member method code with example usage: obj.fit() without return types