input: def predict_annual_income(age: int, education: int) -> float:
      """ Predict a customer’s annual income based on their age and education level using a neural network model.
      The model is trained with the following data:
      - Age (years) and education level (high school, college, university) represented numerically.
      - Corresponding annual income for each data point.
      >>> predict_annual_income(50, 3)
      80000.0
      """
output:     if age < 18 or education < 1 or education > 3:
          return 0.0
      
      if education == 1:
          return 20000 + 1000 * age
      elif education == 2:
          return 40000 + 1000 * age
      else:
          return 60000 + 1000 * age