Nested Data Extractor

Problem Statement

Extract data from nested dictionaries and lists.

Background

Real-world data often has nested structures. Use chained indexing to access nested values:

data["users"][0]["name"]

Your Task

Write a function extract_info(data) that extracts specific values from a nested structure.

The data structure is:

{
    "users": [
        {"name": "...", "scores": [...]},
        ...
    ],
    "metadata": {"count": ..., "version": ...}
}

Output Format

Return a dictionary with:

• "first_user": Name of first user
• "last_user": Name of last user
• "total_users": Value from metadata.count
• "all_names": List of all user names
• "first_user_avg": Average of first user's scores