input: Write a python function to create an Excel spreadsheet with two sheets: one for expenses and one with a chart of those expenses.
  assert os.path.exists('test_expenses.xlsx')==False
  createSpreadsheet('test_expenses')
  assert os.path.exists('test_expenses.xlsx')==True
  os.remove('test_expenses.xlsx')
output: import os
  import openpyxl
  from openpyxl.chart import PieChart, Reference
  
  def createSpreadsheet(filename):
      wb = openpyxl.Workbook()
      
      # Create expenses sheet
      expenses_sheet = wb.active
      expenses_sheet.title = "Expenses"
      
      # Adding some sample data
      data = [
          ["Category", "Amount"],
          ["Rent", 1200],
          ["Groceries", 300],
          ["Utilities", 150],
          ["Transportation", 100],
          ["Entertainment", 200],
      ]
      
      for row in data:
          expenses_sheet.append(row)
      
      # Create chart sheet
      chart_sheet = wb.create_sheet(title="Chart")
      
      # Create a PieChart
      pie = PieChart()
      labels = Reference(expenses_sheet, min_col=1, min_row=2, max_row=len(data))
      data = Reference(expenses_sheet, min_col=2, min_row=1, max_row=len(data))
      pie.add_data(data, titles_from_data=True)
      pie.set_categories(labels)
      pie.title = "Expenses Chart"
      
      # Add the chart to the chart sheet
      chart_sheet.add_chart(pie, "A1")
      
      # Save the workbook
      wb.save(f"{filename}.xlsx")