text: """
  Simple Bar Chart
  ================
  This example shows a basic bar chart created with Altair.
  """
  # category: simple charts
  import altair as alt
  import pandas as pd
  
  data = pd.DataFrame({
      'a': ['A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I'],
      'b': [28, 55, 43, 91, 81, 53, 19, 87, 52]
  })
  
  alt.Chart(data).mark_bar().encode(
      x='a',
      y='b'
  )
  