To extract all valid email addresses from the provided text, we can use a regular expression that matches the standard email address format and then join the matches into a comma-separated list without spaces: ```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 """ pattern = r'[a-zA-Z0-9._%+-]+@[a-zA-Z0-9.-]+\.[a-zA-Z]{2,}' emails = re.findall(pattern, text) comma_separated_emails = ','.join(emails) print(comma_separated_emails) ``` This Python code will produce the following output: ``` john.doe@example.com,jane@smith-family.net,support@company.co.uk,info@subdomain.example.org ``` As requested, this is a comma-separated list without spaces, containing only the valid email addresses extracted from the input text.