code: def _install():
      from ..core import DATAFRAME_TYPE, SERIES_TYPE
  
      for cls in DATAFRAME_TYPE:
          setattr(cls, "join", join)
          setattr(cls, "merge", merge)
  
      for cls in DATAFRAME_TYPE + SERIES_TYPE:
          setattr(cls, "append", append)
  
imports: from .concat import DataFrameConcat, concat
  from .merge import join, merge, DataFrameMerge, DataFrameMergeAlign
  from .append import DataFrameAppend, append
label_desc: Use image node_id 1 for calling a global function with example usage: _install() without return types