import json


def build_keyboard(items):
    """
    Build a keyboard from the notes showing each note id in a row,
    and return the required json to display it
        @items: dictionary with notes to display
    """
    keyboard = [[str(key)] for key in items.keys()]
    reply_markup = {"keyboard": keyboard, "one_time_keyboard": True}
    return json.dumps(reply_markup)