max.py

print('Please enter numbers')
print('You can terminate by entering -1 when you enter as many numbers as you want')

numbers = []

while True:
    num = int(input('Number:'))
    numbers.append(num)

    if num == -1:
        break

max=0
for i in numbers:
    if i > max:
        max = i

print('Largest number:',max)