What version of pycrypto should I use?

As a cryptocurrency and finance professional, I often encounter the need to ensure the security and integrity of our systems. When it comes to cryptography libraries, pycrypto is a popular choice. However, with the constant evolution of technology and security threats, it's crucial to select the appropriate version that best meets our needs. My question is: "Which version of pycrypto should I be using for my current project? Are there any known security vulnerabilities in older versions that I should be aware of? Are there any specific features or improvements in newer versions that could benefit my application? It's important to stay updated with the latest security practices, so I'd like to ensure that I'm using the most secure and efficient version of pycrypto available.