Large lists often contain duplicates, incorrect formats (missing ports), or mixed types (SOCKS4, SOCKS5, HTTP).
If this is a "found" list from a public source, be aware that many may be "honeypots" (monitored by owners) or highly unstable. 70K Proxies.txt
To help you with your file, I need to know exactly how you intend to use it. Proxies are versatile tools, and "developing a piece" for them could mean anything from creating a script to manage them to writing a guide on how to deploy them. Large lists often contain duplicates