I found the solution just in case someone needs the same, for websites which is what I needed (for web applications is easier because there's an installable tool)
Add a registry entry key ".py" in
HKEY_CURRENT_USER\Software\Microsoft\VisualStudio\10.0_Config\Projects{E24C65DC-7377-472b-9ABA-BC803B73C61A}\RelatedFiles.aspx