input: def determine_commission_rate(gross_sales: float) -> float:
      """Given the gross sales, determine and return the commission rate based on the following rules:
      - If gross sales are 10000 or more, the commission rate is 0.1.
      - If gross sales are between 5000 and 9999 (inclusive), the commission rate is 0.07.
      - If gross sales are less than 5000, the commission rate is 0.05.
      >>> determine_commission_rate(12000)
      0.1
      >>> determine_commission_rate(7500)
      0.07
      >>> determine_commission_rate(3000)
      0.05
      """
output:     if gross_sales >= 10000:
          return 0.1
      elif gross_sales >= 5000:
          return 0.07
      else:
          return 0.05