To extract all valid email addresses from the given text, I'll use a regular expression that matches the email format: ```python import re text = """ Contact information: 1. John Doe - john.doe@example.com 2. Jane Smith - jane@smith-family.net 3. support@company.co.uk 4. info@subdomain.example.org 5. Invalid email: not.an.email.com 6. Another invalid: @missing-username.com """ emails = re.findall(r"[a-zA-Z0-9._%+-]+@[a-zA-Z0-9.-]+\.[a-zA-Z]{2,}", text) emails_str = ",".join(emails) print(emails_str) ``` This script will output: ``` john.doe@example.com,jane@smith-family.net,support@company.co.uk,info@subdomain.example.org ``` Here are the extracted email addresses as a comma-separated list without spaces.