WTFPython

wft.py

class Provider:
    def __init__(self, name):
        self.name = name

    def __getattr__(self, attr):
        return Provider(self.name + '.' + str(attr))

    def __rmatmul__(self, other):
        return other + '@' + self.name

gmail = Proviier("gmail")
mail = Provider("mail")
yandex = Provider("yandex")

if __name__ == "__main__":
    print("bob"@gmail.com)
    print("alice"@mail.ru)
    print("carol"@yandex.by)