code: def select_data():
      data_val = data_select.value
      with h5py.File(join(app_dir, "demo_data.hdf5"), "r") as f:
          return f[data_val]["x"][:], f[data_val]["pdf"][:]
  
file_path: bokeh/examples/server/app/simple_hdf5/main.py
imports: import os
  from os.path import dirname, join
  import h5py
  from bokeh.io import curdoc
  from bokeh.layouts import row
  from bokeh.models import ColumnDataSource, Select
  from bokeh.plotting import figure
label_desc: Use image node_id 1 for calling a global function with example usage: select_data() and returns: f,  f