code: def _install():
      from ..core import DATAFRAME_TYPE, SERIES_TYPE, INDEX_TYPE
  
      for cls in DATAFRAME_TYPE + SERIES_TYPE:
          setattr(cls, "fillna", fillna)
          setattr(cls, "ffill", ffill)
          setattr(cls, "pad", ffill)
          setattr(cls, "backfill", bfill)
          setattr(cls, "bfill", bfill)
          setattr(cls, "isna", isna)
          setattr(cls, "isnull", isnull)
          setattr(cls, "notna", notna)
          setattr(cls, "notnull", notnull)
  
      for cls in DATAFRAME_TYPE:
          setattr(cls, "dropna", df_dropna)
          setattr(cls, "replace", df_replace)
  
      for cls in SERIES_TYPE:
          setattr(cls, "dropna", series_dropna)
          setattr(cls, "replace", series_replace)
  
      for cls in INDEX_TYPE:
          setattr(cls, "fillna", index_fillna)
          setattr(cls, "dropna", index_dropna)
          setattr(cls, "isna", isna)
          setattr(cls, "notna", notna)
  
imports: from .fillna import fillna, ffill, bfill, index_fillna
  from .checkna import isna, notna, isnull, notnull
  from .dropna import df_dropna, series_dropna, index_dropna
  from .replace import df_replace, series_replace
label_desc: Use image node_id 1 for calling a global function with example usage: _install() without return types