code: def breast_cancer_split():
      return train_test_split(
          *load_breast_cancer(return_X_y=True),
          test_size=0.1,
          random_state=1,
      )
  
imports: import numpy
  import pandas
  import pytest
  from sklearn.model_selection import train_test_split
  import lightgbm
  from lightgbm.compat import GRAPHVIZ_INSTALLED, MATPLOTLIB_INSTALLED, PANDAS_INSTALLED, pd_DataFrame
  from .utils import load_breast_cancer, make_synthetic_regression
label_desc: Use image node_id 1 for calling a global function with example usage: breast_cancer_split() and returns: train_test_split