pyaria2 is a Python 3 module that provides a wrapper class around Aria2's RPC interface. It can be used to build applications that use Aria2 for downloading data.
aria2 is a lightweight multi-protocol & multi-source command-line download utility. It supports HTTP/HTTPS, FTP, BitTorrent and Metalink. aria2 can be manipulated via built-in JSON-RPC and XML-RPC interfaces.
http://aria2.sourceforge.net/manual/en/html/aria2c.html#rpc-interface