Accessing a variable inside the method of a class

You could simply create a variable inside the __init__() method which gets called as soon as a class is initialized, and then you can change the value of the variable which would get reflected outside the class as well.

It seems that you were trying to create a method save() for the class so I did the same for you, If you don't want your save() method to take any arguments then you can also use def save(self):

class Expense:    def __init__(self):        #Do some initializations here        self.TotalAmount = 0    def save(self, amount):        self.TotalAmount = amountexp = Expense()print exp.TotalAmount>>> 0exp.save(10)print exp.TotalAmount>>> 10

You need to either add the variable as a property on the object (self.TotalAmount = blah) or make it a global variable:

class Expense:  def __init__(self):    def Save(self)       global TotalAmount       TotalAmount = blah

The first solution is the preferred one because having a lot of global variables will make your code hard to read. You should strive for encapsulation because it makes it easier to maintain the code in the future (changing one part of the code is less likely to break other parts).