class Number:
    def __init__(self, value):
        self.value = value
    def __int__(self):
        return self.value
    def __sub__(self, other):
        print("Subtrahiere", self.value, "mit", other.value)
        return self.value - other.value

num1 = Number(13)
num2 = Number(37)

print(num2 - num1)
# Output:
# Subtrahiere 37 mit 13
# 24

print(2 + int(num1))
# Output:
# 15