title: Patching Python packages, installed as dependencies with Pip
body: <p>I have a Python project, which can be installed using Pip. Along with installing the project, Pip downloads and installs some Python packages as dependencies. There's py-amqplib among them. To achieve the desired functionality I need to apply a patch to py-amqplib after its installation. Is there any way to do it automatically in the process of installation of my project?</p>