code: def _import_matplotlib():
      try:
          import matplotlib.pyplot as plt
      except ImportError as e:
          warnings.warn("To draw plots you should install matplotlib.")
          raise ImportError(str(e))
      yield plt
  
imports: from .None import _catboost
  from .core import Pool, CatBoostError, ARRAY_TYPES, PATH_TYPES, fspath, _update_params_quantize_part, _process_synonyms
  from collections import defaultdict
  from contextlib import contextmanager
  import sys
  import numpy
  import warnings
label_desc: Use image node_id 1 for calling a global function with example usage: _import_matplotlib() without return types