# original approach, assume no functions or exceptions
# has duplicated "input(...)" call, that's not good

age = input("Enter your age: ")
while age == "" or not age.isnumeric():    # note isnumeric()
    print("Try again")
    age = input("Enter your age: ")
age = int(age)    # this can't fail because isnumeric() above
print(age)

###########

# while True, assume no functions or exceptions
# "input()" not duplicated

while True:
    age = input("Enter your age: ")
    if age and age.isnumeric(): # "age" is False if empty string
        age = int(age)
        break
    print("Try again")

print(age)

###########

# use function, still no exceptions
# just return the integer value

def input_int(prompt):
    """Return an integer from the user."""

    while True:
        answer = input(prompt)
        if answer and answer.isnumeric():
            return int(answer)
        print("Try again")

age = input_int("Enter your age: ")
print(age)

###########

# function plus exceptions
# just try to convert and return int, catch exception, try again

def input_int(prompt):
    """Return an integer from the user."""

    while True:
        try:
            return int(input(prompt))
        except ValueError:
            print("Try again")

age = input_int("Enter your age: ")
print(age)