You are a helpful assistant. The assistant first thinks about the reasoning process in the mind and then provides the user with the answer. The reasoning process and answer must be formatted exactly as follows:
<think>
[your reasoning process here]
</think>
<answer>
[your answer here]
</answer>
You can choose to imitate the reasoning process of relevant algorithms or explore an appropriate solution on your own. DO NOT use code, and remember to focus on the logical flow.
system
Your task is to solve the Maximum Independent Set problem in the given social network. In this network, each node represents a user, and each edge represents a friendship connection. You need to identify the largest subset of users such that no two users in this subset are friends connected by an edge. 

**Problem to Solve**

- Users in the network: Heather Lynch, Veronica Mcpherson, Sara Wright, Stephen Huff, Stephanie Christensen, Charles Sullivan, Daniel Tyler, Jacob Green, Daniel Santos, Todd Moran, Katherine Patel, Patrick Brown, Timothy Ruiz, Ruth Howell, Sean Lewis, Brett Davis, Jessica Ball, Steve Booth, Gregory Thomas, Kathy Diaz.
- Fiendship connections: Heather Lynch and Stephanie Christensen, Veronica Mcpherson and Stephanie Christensen, Sara Wright and Stephanie Christensen, Stephen Huff and Stephanie Christensen, Stephanie Christensen and Gregory Thomas, Stephanie Christensen and Jessica Ball, Stephanie Christensen and Steve Booth, Stephanie Christensen and Brett Davis, Stephanie Christensen and Kathy Diaz, Stephanie Christensen and Charles Sullivan, Stephanie Christensen and Daniel Tyler, Stephanie Christensen and Jacob Green, Stephanie Christensen and Daniel Santos, Stephanie Christensen and Todd Moran, Stephanie Christensen and Katherine Patel, Stephanie Christensen and Patrick Brown, Stephanie Christensen and Timothy Ruiz, Stephanie Christensen and Ruth Howell, Stephanie Christensen and Sean Lewis, Steve Booth and Kathy Diaz.
Identify the Maximum Independent Set of this network and present your answer in the following format: [UserA, UserB, UserC, UserD, ...].
user
{"directed": false, "multigraph": false, "graph": {}, "nodes": [{"name": "Heather Lynch", "id": 208547}, {"name": "Veronica Mcpherson", "id": 425508}, {"name": "Sara Wright", "id": 65193}, {"name": "Stephen Huff", "id": 186795}, {"name": "Stephanie Christensen", "id": 40748}, {"name": "Charles Sullivan", "id": 306998}, {"name": "Daniel Tyler", "id": 428104}, {"name": "Jacob Green", "id": 428106}, {"name": "Daniel Santos", "id": 428107}, {"name": "Todd Moran", "id": 428108}, {"name": "Katherine Patel", "id": 428109}, {"name": "Patrick Brown", "id": 428110}, {"name": "Timothy Ruiz", "id": 428111}, {"name": "Ruth Howell", "id": 428112}, {"name": "Sean Lewis", "id": 428113}, {"name": "Brett Davis", "id": 21586}, {"name": "Jessica Ball", "id": 8266}, {"name": "Steve Booth", "id": 21207}, {"name": "Gregory Thomas", "id": 1256}, {"name": "Kathy Diaz", "id": 32104}], "links": [{"source": 208547, "target": 40748}, {"source": 425508, "target": 40748}, {"source": 65193, "target": 40748}, {"source": 186795, "target": 40748}, {"source": 40748, "target": 1256}, {"source": 40748, "target": 8266}, {"source": 40748, "target": 21207}, {"source": 40748, "target": 21586}, {"source": 40748, "target": 32104}, {"source": 40748, "target": 306998}, {"source": 40748, "target": 428104}, {"source": 40748, "target": 428106}, {"source": 40748, "target": 428107}, {"source": 40748, "target": 428108}, {"source": 40748, "target": 428109}, {"source": 40748, "target": 428110}, {"source": 40748, "target": 428111}, {"source": 40748, "target": 428112}, {"source": 40748, "target": 428113}, {"source": 21207, "target": 32104}]}
Your task is to solve the Maximum Independent Set problem in the given social network. In this network, each node represents a user, and each edge represents a friendship connection. You need to identify the largest subset of users such that no two users in this subset are friends connected by an edge. 

**Problem to Solve**

- Users in the network: Heather Lynch, Veronica Mcpherson, Sara Wright, Stephen Huff, Stephanie Christensen, Charles Sullivan, Daniel Tyler, Jacob Green, Daniel Santos, Todd Moran, Katherine Patel, Patrick Brown, Timothy Ruiz, Ruth Howell, Sean Lewis, Brett Davis, Jessica Ball, Steve Booth, Gregory Thomas, Kathy Diaz.
- Fiendship connections: Heather Lynch and Stephanie Christensen, Veronica Mcpherson and Stephanie Christensen, Sara Wright and Stephanie Christensen, Stephen Huff and Stephanie Christensen, Stephanie Christensen and Gregory Thomas, Stephanie Christensen and Jessica Ball, Stephanie Christensen and Steve Booth, Stephanie Christensen and Brett Davis, Stephanie Christensen and Kathy Diaz, Stephanie Christensen and Charles Sullivan, Stephanie Christensen and Daniel Tyler, Stephanie Christensen and Jacob Green, Stephanie Christensen and Daniel Santos, Stephanie Christensen and Todd Moran, Stephanie Christensen and Katherine Patel, Stephanie Christensen and Patrick Brown, Stephanie Christensen and Timothy Ruiz, Stephanie Christensen and Ruth Howell, Stephanie Christensen and Sean Lewis, Steve Booth and Kathy Diaz.
Identify the Maximum Independent Set of this network and present your answer in the following format: [UserA, UserB, UserC, UserD, ...].
test