caculator.py

def add():
    print("sum of",a,"and",b,"is: ",a+b)
def diff():
    if a>b:
        print("difference of",a,"and",b,"is: ",a-b)
    else:
        print("difference of",a,"and",b,"is: ",b-a)
def multipy():
    print("multiplication f",a,"and",b,"is: ",a*b)
def div():
    if a==0 or b==0:
        print("division not possible")
        print("division of",a,"and",b,"is: ",a/b)
    else:
        print("division of",a,"and",b,"is: ",a/b)
        
print('1.to add 2 number \n 2.to subtract 2 numbers\n 3. to multipy 2 number \n 4. divide 2 numbers \n 5. exit')
a=float(input('enetr number'))
b=float(input('enter number'))
while True:
    ch=int(input("enter function you want to perform"))
    if ch==1:
        add()
    elif ch==2:
        diff()
    elif ch==3:
        multiply()
    elif ch==4:
        div()
    else:
        break