def insert(self, doc, synced=False):
        doc.id = self.get_next_id()
        doc.synced = synced
        try:
            self.db.docs.insert(doc)
        except Exception as e:
            raise DatabaseException(e)
        return doc
def __init__(self, w, h, color = "empty"):
		self.board = zeros((h,w), dtype=uint8)
		self.w = w
		self.h = h
		self.set_brush(color)