why is the balance after depositing is = None?

I created this simple withdrawal and deposit machine and used a class method for depositing but there seems to be something wrong with it as I expected the return value of the deposit method to be = 20,500 but instead its = None , so what it is the problem here ? and are there any mistakes in my code ?

print("Hello !!! Welcome to Deposit & Withdrawal Machine")
class Account:
withDrawalAmount = 0 
depositAmnt = 0 
def __init__(self, ID=0, balance=100, annual_interest_rate=0):
self.__ID = ID
self.__balance = balance
self.__annual_interest_rate = annual_interest_rate
#setters
def setId(self, ID):
self.__ID = ID
def setBal(self, Bal):
self.__balance = Bal
def setAnnualInterestRate(self, annualIntrstRate):
self.__annual_interest_rate = annualIntrstRate
#getters
def getId(self):
return self.__ID
def getBal(self):
return self.__balance
def getAnnualIntrstRate(self):
return self.__annual_interest_rate
#special getters 
def getMonthlyInterestRate(self):
self.annual_rate = self.__annual_interest_rate / 100
self.monthly_rate = self.annual_rate / 12
return self.monthly_rate
def getMonthlyInterest(self):
return self.__balance * self.monthly_rate
#other methods
def withdraw(self, withDrawalAmount):
if self.__balance >= self.withDrawalAmount:
self.__balance = self.__balance - self.withDrawalAmount 
return self.__balance
def deposit(self, depositAmnt ):
if self.depositAmnt >=  1 :
self.__balance = self.__balance + self.depositAmnt
return self.__balance
client001 = Account(1122, 20000, 4.5)
print("Your Balance After withdrawal is : ", client001.withdraw(2500))
print("Your Balance After deposit is : ", client001.deposit(3000))
print("Your Account ID is : ", client001.getId())
print("Your Current Balance is : ", client001.getBal())
print("Your Monthly Intrst Rate is : ", client001.getMonthlyInterestRate())
print("Your Monthly intrst is : ", client001.getMonthlyInterest())

def deposit (self , depositAmnt ):
if self.depositAmnt >=  1 :
self.__balance = self.__balance + self.depositAmnt
return self.__balance

The amount being deposited is depositAmnt, not self.depositAmnt.

So the if condition is false, therefore the function does not return anything, therefore it returns None by default.

As John already mentioned, to rectify this you need to use the variable depositAmnt in your if statement.

    def deposit (self , depositAmnt ):
if depositAmnt >=  1 :
self.__balance = self.__balance + depositAmnt
return self.__balance

right now, the attributes of your class -withDrawalAmount and depositAmnt don't have any usage (since you are inputting them as an argument in your function deposit and withdraw.

You should also change the withdraw function as:

def withdraw (self , withDrawalAmount):
if self.__balance >= withDrawalAmount:
self.__balance = self.__balance - withDrawalAmount 
return self.__balance