from notation import Notation


class One(Notation):

    def run(self, n):
        self.add_step()
        result = n * (n + 1) / 2
        self.set_result(result)

a4be323e5320c3da7ab3cc2d9554950c0a029364
<mask token>

<mask token>


class One(Notation):
    <mask token>

<mask token>


class One(Notation):

    def run(self, n):
        self.add_step()
        result = n * (n + 1) / 2
        self.set_result(result)

from notation import Notation


class One(Notation):

    def run(self, n):
        self.add_step()
        result = n * (n + 1) / 2
        self.set_result(result)
