使用python写一个房贷计算器，需要写注释

# 导入math库，用于计算幂函数
import math

# 定义房贷计算器类
class MortgageCalculator:

# 初始化函数，传入贷款总额、贷款年限和年利率三个参数
def __init__(self, loan_amount, loan_term, interest_rate):
self.loan_amount = loan_amount
self.loan_term = loan_term
self.interest_rate = interest_rate

# 计算每月还款额
def monthly_payment(self):
# 将年利率转换为月利率
monthly_rate = self.interest_rate / 12
# 计算每月还款额
monthly_payment = self.loan_amount * monthly_rate * math.pow(1 + monthly_rate, self.loan_term * 12) / (math.pow(1 + monthly_rate, self.loan_term * 12) - 1)
return monthly_payment

# 计算还款总额
def total_payment(self):
total_payment = self.monthly_payment() * self.loan_term * 12
return total_payment

# 计算支付利息总额
def total_interest(self):
total_interest = self.total_payment() - self.loan_amount
return total_interest

# 输出计算结果
def print_result(self):
print('贷款总额：%.2f元' % self.loan_amount)
print('贷款年限：%d年' % self.loan_term)
print('年利率：%.2f%%' % (self.interest_rate * 100))
print('每月还款额：%.2f元' % self.monthly_payment())
print('还款总额：%.2f元' % self.total_payment())
print('支付利息总额：%.2f元' % self.total_interest())

# 示例代码，计算贷款总额为100万元，贷款年限为20年，年利率为5%的房贷计算器
mortgage_calculator = MortgageCalculator(1000000, 20, 0.05)
mortgage_calculator.print_result()