text: Title: Timezones in fbprophet
  Body: Due to this issue https://github.com/facebook/prophet/issues/831
  
  topic 9 part 2 notebook needs to be changed a bit:
  
  df = daily_df.reset_index()
  df.columns = ['ds', 'y']
  **df['ds'] = df['ds'].dt.tz_convert(None)**
  
  
  