here are three models named ##pdl1 detection model##, ##ki67 detection model##,  ##her2 detection model##, you should  choose one of them according to the user intent, and you should only output the name of the model , do not provide any other information. the user input is "can you count the positive cell in this pdl1"
 Write exactly 5 paragraphs each separated with two new lines answering this question. The 4th paragraph must start with "contact".
user