Any way to change source code for debugging?

[2niuhe]

As a developer,I wanna change some code under the path

snap/microstack/196/lib/python3.6/site-package

but the file system of snap is read-only,I cannot change the source code such as add

import pdb;pdb.set_trace()

to the code,and debug it .

Now I only can change some config file under /var/snap/microstack/common/etc/.

So I wanna ask ,Is there any way to change the source code easily .It's essential for debugging.

Thanks.