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![sunil shrestha](https://secure.gravatar.com/avatar/be08773abf009a5a2834a4a24d4b2b84?s=96&d=https%3A%2F%2Fecs-static.teamtreehouse.com%2Fassets%2Fcontent%2Fdefault_avatar-445fbbabfc8dc9188fb5967fe43322ee0c3e0dd1e10f378bf8343784af5a13eb.webp&r=pg)
sunil shrestha
735 PointsI didn't understand self.assertEqual(self.rock, Rock()) .
if ROck() is an instance as said by kenneth sir, how does any instance contain parenthesis .
1 Answer
![Steven Parker](https://uploads.teamtreehouse.com/production/profile-photos/969492/micro_tool_chess_set_2.jpg)
Steven Parker
230,688 PointsPutting parentheses after a class name creates a new instance of that class.
The line you show actually causes an error which is discovered later in the video, and then Rock()
is replaced with moves.Rock()
.