code: def fit(self, X, y=None):
      self.X_ = X
      self.n_features_ = X.shape[0]
      return self
  
imports: from functools import partial
  import numpy
  import pytest
  from numpy.testing import assert_allclose
  from sklearn._config import config_context
  from sklearn.base import BaseEstimator
  from sklearn.utils._array_api import _ArrayAPIWrapper, _asarray_with_order, _atol_for_type, _convert_to_numpy, _estimator_with_converted_arrays, _nanmax, _nanmin, _NumPyAPIWrapper, _weighted_sum, get_namespace, supported_float_dtypes, yield_namespace_device_dtype_combinations
  from sklearn.utils._testing import _array_api_for_tests, skip_if_array_api_compat_not_configured
label_desc: Use image node_id 1 for calling the SimpleEstimator obj's underlying member method code with example usage: obj.fit(X, y) and returns: self