def add(a, b):
    return a + b


def mul(a, b):
    return a * b


def div(a, b):
    return a / b


if __name__ == "__main__":
    print("{}, {}".format('hello python', 'hi pycharm'))
    x = 10
    y = 5
    print("add({}, {}) = {}\n".format(x, y, add(x, y)))
    print("mul({}, {}) = {}\n".format(x, y, mul(x, y)))
    print("div({}, {}) = {}\n".format(x, y, div(x, y)))