input: Write a function to take a list of email addresses as input and return a filtered list of email addresses that belong to a particular domain. The function should accept an additional parameter specifying the domain to filter by. If no domain is provided, it should default to "@gmail.com".
  def filter_emails_by_domain(email_list, domain="@gmail.com"):
      return [email for email in email_list if email.endswith(domain)]
  
  assert filter_emails_by_domain(["john@gmail.com", "sarah@yahoo.com", "bob@microsoft.com", "sophie@gmail.com"]) == ["john@gmail.com", "sophie@gmail.com"]
  assert filter_emails_by_domain(["john@gmail.com", "sarah@yahoo.com", "bob@microsoft.com", "sophie@gmail.com"], "@yahoo.com") == ["sarah@yahoo.com"]
  assert filter_emails_by_domain(["john@gmail.com", "sarah@yahoo.com", "bob@microsoft.com", "sophie@gmail.com"], "@microsoft.com") == ["bob@microsoft.com"]
  assert filter_emails_by_domain([]) == []
output: def filter_emails_by_domain(email_list, domain="@gmail.com"):
      return [email for email in email_list if email.endswith(domain)]