  Open source projects are adopting faster release cycles that reflect various
changes. Therefore, comprehending the effects of these changes on software's
architecture over the releases becomes necessary. However, it is challenging to
keep architecture in-check and add new changes simultaneously for every
release. To this end, we propose a visualization tool called AC2, which allows
its users to examine the alterations in the architecture at both higher and
lower levels of abstraction for the python projects. AC2 uses call graphs and
collaboration graphs to show the interaction between different architectural
components. The tool provides four different views to see the architectural
changes. The user can examine two releases at a time to comprehend the
architectural changes between the releases. AC2 can support the maintainers and
developers to observe changes in the project and its influence on the
architecture, which allow them to see its increasing complexity over the
releases at the component level. AC2 can be downloaded at
https://github.com/dheerajrox/AC2 and its demo can be seen at the website
https://dheerajrox.github.io/AC2doc or on youtube
https://www.youtube.com/watch?v=GNrJfZ0RCVI
