19.py

# example 1
try:
    age=int(input("enter the age:"))
    if age < 0:
        print('age cannot be negative')
    else:
        years_left=100-age
        if years_left>0:
            print(f"you will be 100 years old in {years_left} years.")
        elif years_left==0:
            print("your already 100 years old.")
        else:
            print("your already over 100 years")
except ValueError:
    print("Invalid input , please enter a valid input")


# example 2

try:
    a=int(input("enter a value:"))
    b=int(input("enter b value:"))
    c=a/b
    print("sucsess",c)
except ZeroDivisionError:
    print("zero division errror")
except ValueError:
    print("please enter a valid input")

#example 3
try:
    filename=input('enter a file name:')
    file=open(filename,'r') 
    content=file.read()
    file.close()
except FileNotFoundError:
    print('Error File does not exist.')

finally:
    print("program end")