diff --git a/Calculator with simple ui.py b/Calculator with simple ui.py
index eb0a5b727a2..122156a3cfd 100644
--- a/Calculator with simple ui.py	
+++ b/Calculator with simple ui.py	
@@ -1,23 +1,73 @@
 # Program make a simple calculator
 
-# This function adds two numbers
-def add(x, y):
-    return x + y
 
-# This function subtracts two numbers
-def subtract(x, y):
-    return x - y
+class Calculator:
+    def __init__(self):
+        pass
 
-# This function multiplies two numbers
-def multiply(x, y):
-    return x * y
+    def add(self, num1, num2):
+        """
+        This function adds two numbers.
 
-# This function divides two numbers
-def divide(x, y):
-    return x / y
+        Examples:
+        >>> add(2, 3)
+        5
+        >>> add(5, 9)
+        14
+        >>> add(-1, 2)
+        1
+        """
+        return num1 + num2
+
+    def subtract(self, num1, num2):
+        """
+        This function subtracts two numbers.
+
+        Examples:
+        >>> subtract(5, 3)
+        2
+        >>> subtract(9, 5)
+        4
+        >>> subtract(4, 9)
+        -5
+        """
+        return num1 - num2
+
+    def multiply(self, num1, num2):
+        """
+        This function multiplies two numbers.
+
+        Examples:
+        >>> multiply(4, 2)
+        8
+        >>> multiply(3, 3)
+        9
+        >>> multiply(9, 9)
+        81
+        """
+        return num1 * num2
+
+    def divide(self, num1, num2):
+        """
+        This function divides two numbers.
+
+        Examples:
+        >>> divide(4, 4)
+        1
+        >>> divide(6, 3)
+        2
+        >>> divide(9, 1)
+        9
+        """
+        if num2 == 0:
+            print("Cannot divide by zero")
+        else:
+            return num1 / num2
+
+
+calculator = Calculator()
 
 
-print("Select operation.")
 print("1.Add")
 print("2.Subtract")
 print("3.Multiply")
@@ -28,22 +78,21 @@ def divide(x, y):
     choice = input("Enter choice(1/2/3/4): ")
 
     # Check if choice is one of the four options
-    if choice in ('1', '2', '3', '4'):
+    if choice in ("1", "2", "3", "4"):
         num1 = float(input("Enter first number: "))
         num2 = float(input("Enter second number: "))
 
-        if choice == '1':
-            print(num1, "+", num2, "=", add(num1, num2))
+        if choice == "1":
+            print(calculator.add(num1, num2))
 
-        elif choice == '2':
-            print(num1, "-", num2, "=", subtract(num1, num2))
+        elif choice == "2":
+            print(calculator.subtract(num1, num2))
 
-        elif choice == '3':
-            print(num1, "*", num2, "=", multiply(num1, num2))
+        elif choice == "3":
+            print(calculator.multiply(num1, num2))
 
-        elif choice == '4':
-            print(num1, "/", num2, "=", divide(num1, num2))
+        elif choice == "4":
+            print(calculator.divide(num1, num2))
         break
     else:
         print("Invalid Input")
-