code: def test_float_fail():
      y = np.array([1, 2], dtype=np.int_)
      reg = BlankRegressor()
      assert_raises(
          AttributeError,
          f"y must be a float array.\nFound {str(y.dtype)}",
          reg._check_target_array,
          y,
      )
  
file_path: mlxtend/mlxtend/_base/tests/test_regressor.py
imports: import numpy
  from mlxtend._base import _BaseModel, _Regressor
  from mlxtend.utils import assert_raises
label_desc: Use image node_id 2 for calling a global function with example usage: test_float_fail() without return types