Please read the following table in Markdown format and then answer the question according to the table. Table cells in one row are seperated by '|', and different rows are seperated by '
'.

Table:
| Year | Game | Genre | Platform(s) | Developer(s) |
| --- | --- | --- | --- | --- |
| 2007.0 | Portal | Puzzle , first-person shooter , science fiction | Xbox 360 , PlayStation 3 , Windows | Valve Corporation |
| 2008.0 | Braid | Puzzle , platformer | Xbox Live Arcade , PlayStation Network | Number None, Inc. |
| 2009.0 | Uncharted 2: Among Thieves | Action-adventure , third-person shooter | PlayStation 3 | Naughty Dog |
| 2010.0 | Red Dead Redemption | Open World , third-person shooter | Xbox 360 , PlayStation 3 | Rockstar San Diego |
| 2011.0 | The Elder Scrolls V: Skyrim | Action RPG | Xbox 360 , PlayStation 3 , Windows | Bethesda Game Studios |
| 2012.0 | Mass Effect 3 | Action RPG , third-person shooter | Xbox 360 , PlayStation 3 , Windows | BioWare |
Question:
Who were the developers for Portal?
Answer:
Valve Corporation