code: def update_plot(attrname, old, new):
      city = city_select.value
      plot.title.text = "Weather data for " + cities[city]["title"]
  
      src = get_dataset(
          df, cities[city]["airport"], distribution_select.value
      )
      source.data.update(src.data)
  
file_path: bokeh/examples/server/app/weather/main.py
imports: import datetime
  from os.path import dirname, join
  import pandas
  from scipy.signal import savgol_filter
  from bokeh.io import curdoc
  from bokeh.layouts import column, row
  from bokeh.models import ColumnDataSource, DataRange1d, Select
  from bokeh.palettes import Blues4
  from bokeh.plotting import figure
label_desc: Use image node_id 3 for calling a global function with example usage: update_plot(attrname, old, new) without return types